<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Publishing DTD v1.3 20210610//EN" "https://jats.nlm.nih.gov/publishing/1.3/JATS-journalpublishing1-3.dtd"><article xml:lang="en" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" dtd-version="1.3" article-type="research-article"><front><journal-meta><journal-id journal-id-type="issn">2460-0245</journal-id><journal-title-group><journal-title>Journal of the Indonesian Mathematical Society</journal-title><abbrev-journal-title>JIMS</abbrev-journal-title></journal-title-group><issn pub-type="epub">2460-0245</issn><issn pub-type="ppub">2086-8952</issn><publisher><publisher-name>IndoMS</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.22342/jims.v32i2.1822</article-id><article-categories></article-categories><title-group><article-title>Inequality Estimations of Subclass of Univalent Functions Involving Raducanu-Orhan Operator</article-title></title-group><contrib-group><contrib contrib-type="author"><name><surname>Manickam</surname><given-names>Thirucheran</given-names></name><address><country country="IN">India</country><email>drstalint@veltech.edu.in</email></address><xref ref-type="aff" rid="AFF-1"></xref></contrib><contrib contrib-type="author"><name><surname>Kumar</surname><given-names>Saravanan</given-names></name><address><country country="IN">India</country><email>drstalint@veltech.edu.in</email></address><xref ref-type="aff" rid="AFF-2"></xref></contrib><contrib contrib-type="author"><name><surname>Ramachandran</surname><given-names>Navaneetha Krishnan</given-names></name><address><country country="IN">India</country><email>drstalint@veltech.edu.in</email></address><xref ref-type="aff" rid="AFF-3"></xref></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-8735-3567</contrib-id><name><surname>Thangamani</surname><given-names>Stalin</given-names></name><address><country country="IN">India</country><email>drstalint@veltech.edu.in</email></address><xref ref-type="aff" rid="AFF-3"></xref><xref ref-type="corresp" rid="cor-0"></xref></contrib><contrib contrib-type="author"><name><surname>Pandi</surname><given-names>Boopathy</given-names></name><address><country country="IN">India</country><email>drstalint@veltech.edu.in</email></address><xref ref-type="aff" rid="AFF-4"></xref></contrib></contrib-group><contrib-group><contrib contrib-type="editor"><name><surname>abdurahim</surname></name><address><country country="ID">Indonesia</country><email>abdurahim@staff.unram.ac.id</email></address></contrib><contrib contrib-type="editor"><name><surname>Rizal</surname><given-names>Jose</given-names></name><address><email>jrizal04@unib.ac.id</email></address></contrib></contrib-group><aff id="AFF-1"><institution content-type="dept">Department of Mathematics</institution><country>L N Government College</country></aff><aff id="AFF-2"><institution content-type="dept">Department of Mathematics</institution><country>Dr Ambedkar Government Arts College</country></aff><aff id="AFF-3"><institution content-type="dept">Department of Mathematics</institution><institution-wrap><institution>Vel Tech Rangarajan Dr. Sagunthala R&amp;D Institute of Science and Technology</institution><institution-id institution-id-type="ror">https://ror.org/05bc5bx80</institution-id></institution-wrap><country country="IN">India</country></aff><aff id="AFF-4"><institution content-type="dept">Department of Computer Science</institution><country>Anna University Regional Campus</country></aff><author-notes><corresp id="cor-0">Corresponding author: Stalin Thangamani. Email: <email>drstalint@veltech.edu.in</email></corresp></author-notes><pub-date date-type="pub" iso-8601-date="2026-04-27" publication-format="electronic"><day>27</day><month>04</month><year>2026</year></pub-date><pub-date date-type="collection" iso-8601-date="2026-04-23" publication-format="electronic"><day>23</day><month>04</month><year>2026</year></pub-date><volume>32</volume><issue>2</issue><issue-title>JUNE</issue-title><fpage>1</fpage><lpage>21</lpage><history><date date-type="received" iso-8601-date="2024-10-02"><day>02</day><month>10</month><year>2024</year></date><date date-type="accepted" iso-8601-date="2026-03-01"><day>01</day><month>03</month><year>2026</year></date></history><permissions><copyright-statement>Copyright (c) 2026 Journal of the Indonesian Mathematical Society</copyright-statement><copyright-year>2026</copyright-year><copyright-holder>Journal of the Indonesian Mathematical Society</copyright-holder><license xlink:href="https://creativecommons.org/licenses/by-nc-nd/4.0/"><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by-nc-nd/4.0/</ali:license_ref><license-p>This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.</license-p></license></permissions><self-uri xlink:href="https://jims-a.org/index.php/jimsa/article/view/1822" xlink:title="1822"></self-uri><abstract><p>The vast number of new papers that have been written about the univalent function in recent years shows how fascinating it is. Univalent functions are injective analytic functions, which means that they do not take the same value at various places within their domain. Univalent functions are important in complex analysis and have many uses in other areas of mathematics, physics, and engineering. These days, there is a high need for operators of normalized analytic functions, particularly differential and integral operator. Operators are widely used in numerous mathematical and scientific domains. Differential equations can be solved using these operators, which are also used to describe a wide range of physical phenomena.</p></abstract><kwd-group><kwd>univalent functions</kwd><kwd>differential operator</kwd><kwd>coefficient inequality</kwd><kwd>Fekete-Szego inequality</kwd><kwd>subordination</kwd></kwd-group><custom-meta-group><custom-meta><meta-name>File created by JATS Editor</meta-name><meta-value>https://jatseditor.com</meta-value></custom-meta><custom-meta><meta-name>issue-created-year</meta-name><meta-value>2026</meta-value></custom-meta></custom-meta-group></article-meta></front><body><p>Many researchers have reviewed and discussed a substantial amount of material for the operators. In this work, the new subclass of univalent functions is defined by the Raducanu-Orhan differential operator. In addition, the coefficient inequalities, extreme points, integral means of inequality, and Fekte-Szego inequality for the subclass have been obtained.</p><sec id="sec-1"><title>1. INTRODUCTION</title><p>A univalent analytic function, sometimes called a univalent function of a complex variable, is an analytic function that is also univalent, meaning it is a one-to-one. In many branches of mathematics, such as diferential equations and complex analysis, uniform functions play a significant role because of their unique characteristics and uses. For example, univalent functions can be used to express conformal mappings, which maintain angles locally; they are particularly relevant in complex analysis. In complex analysis, the study of the class of univalent functions is important because it has links to many other areas, including the theory of special functions, geometric function theory, and conformal mapping. To gain a better understanding of these functions’ behavior and applicability in other mathematical domains, researchers frequently examine aspects of these functions, such as growth requirements, distortion theorems, and coeficient bounds. In recent years, researchers have been interested in defining a new subclass of univalent analytic functions associated with diferential operators [<xref ref-type="bibr" rid="BIBR-1">1</xref>, <xref ref-type="bibr" rid="BIBR-2">2</xref>, <xref ref-type="bibr" rid="BIBR-3">3</xref>, <xref ref-type="bibr" rid="BIBR-4">4</xref>, <xref ref-type="bibr" rid="BIBR-5">5</xref>] because it has many applications in mathematics, physics, and engineering. The core challenges in the theory of univalent functions are comprehending the limit correspondence in conformal mapping, figuring out univalent requirements, and addressing numerous functional extreme theory problems. More precisely, defining limits on a range of values for various functions in a given class.</p><p>The first substantial results in the theory of univalent functions were obtained using the area principle. With the aid of the outer area theorem (1916), Bieberbach <xref ref-type="bibr" rid="BIBR-6">[6]</xref> obtained precise upper and lower bounds for <inline-formula><tex-math id="math-1"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle | f ( z ) | \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-2"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| f ^ { \prime } ( z ) \right| \end{document} ]]></tex-math></inline-formula> for <inline-formula><tex-math id="math-3"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { S } } \end{document} ]]></tex-math></inline-formula>, provided <inline-formula><tex-math id="math-4"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle | a _ { 2 } | \le 2 \end{document} ]]></tex-math></inline-formula> and conjectured that <inline-formula><tex-math id="math-5"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left. | a _ { n } | \right. \leq n \end{document} ]]></tex-math></inline-formula> . He also found the exact value of the Koebe <xref ref-type="bibr" rid="BIBR-7">[7]</xref> constant. For a long time, mathematicians have been challenged by this conjecture. Louis De Branges <xref ref-type="bibr" rid="BIBR-8">[8]</xref> found a solution to the conjecture <inline-formula><tex-math id="math-6"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle | a _ { n } | \leq n , ( n = 2 , 3 , \ldots ) \end{document} ]]></tex-math></inline-formula> in 1984. Following Loewner <xref ref-type="bibr" rid="BIBR-9">[9]</xref>’s 1923 proof of <inline-formula><tex-math id="math-7"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle | a _ { 3 } | \le 3 \end{document} ]]></tex-math></inline-formula>, Fekete-Szego <xref ref-type="bibr" rid="BIBR-10">[10]</xref> astounded mathematicians with the troublesome inequality <inline-formula><tex-math id="math-8"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle | a _ { 3 } - \eta a _ { 2 } ^ { 2 } | \leq 1 + 2 e ^ { \left( \frac { - 2 \eta } { 1 - \eta } \right) } , \ 0 \leq \eta \leq 1 \end{document} ]]></tex-math></inline-formula>. In recent years, the study of geometric properties of holomorphic functions has gained significant attention due to its applications in geometric function theory and univalent function classes. One key inequality in this field is the Fekete-Szeg¨o inequality, which provides sharp bounds for coeficients in certain classes of analytic functions. This paper focuses on extending these inequalities to more generalized domains using the Raducanu-Orhan operator, which has shown promise in preserving univalent functions across complex order starlike and convex classes. Moreover, we explore the implications of these findings, a special class of conformal maps with unique geometric properties.</p><p>A univalent function that is analytic in a domain and is also referred to as a one-to-one or injective function in complex analysis is said to be conformal. Locally, angles are preserved by conformal mappings. Formally speaking, if a function <inline-formula><tex-math id="math-9"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \end{document} ]]></tex-math></inline-formula> defined in a domain <inline-formula><tex-math id="math-10"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle D \subset C \end{document} ]]></tex-math></inline-formula> maintains the angles between the curves that pass through <inline-formula><tex-math id="math-11"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle z \end{document} ]]></tex-math></inline-formula>, then <inline-formula><tex-math id="math-12"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle z \in D \end{document} ]]></tex-math></inline-formula> is conformal at that point. A function is conformal in a domain <inline-formula><tex-math id="math-13"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle D \end{document} ]]></tex-math></inline-formula> if it is both univalent (injective) and analytic in <inline-formula><tex-math id="math-14"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle D \end{document} ]]></tex-math></inline-formula>. In line with conformal maps in complex analysis, this indicates that the mapping maintains the local structure of the domain locally by not distorting the angles between curves. Conformal mapping is a crucial method in complex analysis with a wide range of real-world applications.</p><p>If the function is harmonic, that is, it satisfies <inline-formula><tex-math id="math-15"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \nabla ^ { 2 } f = 0 \end{document} ]]></tex-math></inline-formula> according to Laplace, then the conformal mapping transformation of such functions is likewise harmonic. Therefore, conformal mapping can be used to solve equations related to any field that can be represented by a potential function. Many problems arising from fluid mechanics, electrostatics, heat conduction, and many other physical situations can be formulated mathematically using Laplace’s equation <inline-formula><tex-math id="math-16"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \phi _ { x x } + \phi _ { y y } = 0 \end{document} ]]></tex-math></inline-formula> in a certain region D of the <inline-formula><tex-math id="math-17"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle z \end{document} ]]></tex-math></inline-formula>-plane. For example, it can be applied to scattering and difraction problems, brain surface mapping problems, and electrostatic potential problems in the shaded region of the <inline-formula><tex-math id="math-18"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle z \end{document} ]]></tex-math></inline-formula>-plane <xref ref-type="bibr" rid="BIBR-11">[11]</xref>. It can also be used in stealth technology. Although the concept of conformal mapping is not directly used in stealth technology, the development of efective stealth technologies greatly benefits from an understanding of shape optimization, material science, and electromagnetic wave behaviour <xref ref-type="bibr" rid="BIBR-12">[12]</xref>. In addition, the univalent function helps to analyze the frequency analysis problem <xref ref-type="bibr" rid="BIBR-13">[13]</xref>.</p><p>In recent years, new subclasses have been defined by using the linear diferential operators. The diferential operator was first introduced by Ruscheweyh <xref ref-type="bibr" rid="BIBR-14">[14]</xref> in 1975, which cleared the path. Salagean <xref ref-type="bibr" rid="BIBR-15">[15]</xref> followed in 1983 with an additional variation of diferential and integral operators. Many scholars have examined and debated a wide range of properties related to these two operators. Al-Oboudi <xref ref-type="bibr" rid="BIBR-16">[16]</xref> generalized the Salagean operator in 2004. In 2010, Raducanu and Orhan <xref ref-type="bibr" rid="BIBR-17">[17]</xref> generalized the Al-Oboudi diferential operator. In this study, we define two new subclasses, which are defined by the Raducanu-Orhan diferential operator. Also, we have discussed some properties of these subclasses.</p><p>Let <inline-formula><tex-math id="math-19"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { A } } \end{document} ]]></tex-math></inline-formula> be the class of univalent functions consisting of the form</p><disp-formula id="equation-1"><tex-math id="math-20"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f (z) = z + \sum_ {\nu = 2} ^ {\infty} a _ {\nu} z ^ {\nu}, z \in \mathbb {U} := \{z \in \mathbb {C}: | z | < 1 \},\tag{1} \end{document} ]]></tex-math></disp-formula><p>which is analytic in the unit disk <inline-formula><tex-math id="math-21"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathbb {U} \end{document} ]]></tex-math></inline-formula>.</p><p>For <inline-formula><tex-math id="math-22"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula>, the Raducanu-Orhan <xref ref-type="bibr" rid="BIBR-17">[17]</xref> diferential operator is defined as <inline-formula><tex-math id="math-23"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathcal { R } _ { \tau , \eta } ^ { n } f ( z ) \end{document} ]]></tex-math></inline-formula>, then</p><disp-formula id="equation-2"><tex-math id="math-24"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{align*}\mathcal{R}_{\tau,\eta}^0 &= f(z) = z + \sum_{\nu=2}^{\infty} a_{\nu} z^{\nu}, \\\mathcal{R}_{\tau,\eta}^1 &= (1 - \tau + \eta) f(z) + (\tau - \eta) z f'(z) + (\tau\eta) z^2 f''(z) \\&= z + \sum_{\nu=2}^{\infty} [1 + (\nu - 1)(\tau - \eta + \nu\tau\eta)] a_{\nu} z^{\nu} \\\mathcal{R}_{\tau,\eta}^2 &= \mathcal{R}_{\tau,\eta} (\mathcal{R}_{\tau,\eta}).\end{align*} \end{document} ]]></tex-math></disp-formula><p>Similarly,</p><disp-formula id="equation-3"><tex-math id="math-25"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathcal {R} _ {\tau , \eta} ^ {n} = \mathcal {R} _ {\tau , \eta} \left(\mathcal {R} _ {\tau , \eta} ^ {n - 1}\right) = z + \sum_ {\nu = 2} ^ {\infty} \left[ 1 + (\nu - 1) (\tau - \eta + \nu \tau \eta) \right] ^ {n} a _ {\nu} z ^ {\nu}. \end{document} ]]></tex-math></disp-formula><p>Hence,</p><disp-formula id="equation-4"><tex-math id="math-26"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathcal {R} _ {\tau , \eta} ^ {n} f (z) = \mathcal {R} _ {\tau , \eta} \left(\mathcal {R} _ {\tau , \eta} ^ {n - 1}\right) = z + \sum_ {\nu = 2} ^ {\infty} [ 1 + (\nu - 1) (\tau - \eta + \nu \tau \eta) ] ^ {n} a _ {\nu} z ^ {\nu},\tag{2} \end{document} ]]></tex-math></disp-formula><p>where <inline-formula><tex-math id="math-27"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle n \in \mathbb { N } _ { 0 } = \mathbb { N } \cup 0 , \mathbb { N } = \{ 1 , 2 , . . . , \} , ~ \eta , ~ \tau \geq 0 , z \in \mathbb { U } . \end{document} ]]></tex-math></inline-formula></p><p>Remark 1.1.</p><list list-type="bullet"><list-item><p><inline-formula><tex-math id="math-28"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathcal { R } _ { \tau , 0 } ^ { n } = \mathcal { D } ^ { n } \end{document} ]]></tex-math></inline-formula><italic>yields the of Al-Oboudi derivative operator</italic><xref ref-type="bibr" rid="BIBR-16">[16]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-29"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathcal { R } _ { 1 , 0 } ^ { n } = \mathcal { D } ^ { n } \end{document} ]]></tex-math></inline-formula><italic>gives Salagean derivative operator </italic><xref ref-type="bibr" rid="BIBR-15">[15]</xref>.</p></list-item></list></sec><sec id="sec-2"><title>2. MAIN RESULTS</title><sec id="sec-3"><title>2.1. The subclasses { \mathcal { S } } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) and { \mathcal { S} } _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ).</title><p><bold>Definition 2.1. </bold><italic>Let </italic><inline-formula><tex-math id="math-30"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula><italic> denote the subclass of </italic><inline-formula><tex-math id="math-31"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> consisting of a function </italic><inline-formula><tex-math id="math-32"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \end{document} ]]></tex-math></inline-formula><italic> which satisfies the inequality</italic></p><disp-formula id="equation-5"><tex-math id="math-33"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle R e \left(1 + \frac {1}{b} \left(\frac {R _ {\delta , \mu} ^ {m} f (z)}{R _ {\delta , \mu} ^ {n} f (z)} - 1\right)\right) > \alpha ,\tag{3} \end{document} ]]></tex-math></disp-formula><p>for <inline-formula><tex-math id="math-34"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b \in \mathbb { C } - \left\{ 0 \right\} , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } , \delta , \mu \geq 0 , 0 \leq \alpha < 1 \end{document} ]]></tex-math></inline-formula>, and for all <inline-formula><tex-math id="math-35"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle z \in \mathbb { U } \end{document} ]]></tex-math></inline-formula>.</p><p>Several well-known subclasses of functions are special cases of <inline-formula><tex-math id="math-36"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> for suitable choices of the parameters, and are listed below.</p><list list-type="bullet"><list-item><p><inline-formula><tex-math id="math-37"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , 0 , \delta , 0 } ^ { m , n } ( \alpha ) { = } S _ { b , m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula> studied by Thiruchran and Stalin <xref ref-type="bibr" rid="BIBR-18">[18]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-38"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { 1 , 0 , 1 , 0 } ^ { m , n } ( \alpha ) { = } K _ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> studied by Sumer Eker and Owa <xref ref-type="bibr" rid="BIBR-19">[19]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-39"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { 1 . 0 . \delta . 0 } ^ { m , n } ( \alpha ) { = } S _ { m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula> studied by Sumer Eker and Ozlem Guney <xref ref-type="bibr" rid="BIBR-20">[20]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-40"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { 1 , 0 , \delta , 0 } ^ { n + 1 , n } ( \alpha ) { = } S _ { n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> studied by Kadioglu <xref ref-type="bibr" rid="BIBR-21">[21]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-41"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { 1 , 0 , 1 , 0 } ^ { 1 , 0 } ( \alpha ) { = } S ^ { * } ( \alpha ) \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-42"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle S _ { 1 , 2 , 1 , 1 } ( \alpha ) = K ( \alpha ) \end{document} ]]></tex-math></inline-formula> studied by H. Silverman <xref ref-type="bibr" rid="BIBR-22">[22]</xref>.</p></list-item></list><p><bold>Theorem 2.2.  </bold><italic>Let </italic><inline-formula><tex-math id="math-43"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> satisfies</italic></p><disp-formula id="equation-6"><tex-math id="math-44"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {j = 2} ^ {\infty} \phi (\alpha) | a _ {j} | \leq 2 (1 - \alpha) b,\tag{4} \end{document} ]]></tex-math></disp-formula><p>for some <inline-formula><tex-math id="math-45"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b \in \mathbb { C } - \left\{ 0 \right\} , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } , \delta , \mu \geq 0 , 0 \leq \alpha < 1 \end{document} ]]></tex-math></inline-formula>, then <inline-formula><tex-math id="math-46"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \in \mathcal { S } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> where</p><disp-formula id="equation-7"><tex-math id="math-47"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array}{c} \phi (\alpha) = | (1 + (j - 1) (\delta - \mu + j \delta \mu)) ^ {m} - (1 + \alpha b) (1 + (j - 1) (\delta - \mu + j \delta \mu)) ^ {n} | \\ \qquad + (1 + (j - 1) (\delta - \mu + j \delta \mu)) ^ {m} + ((2 - \alpha) b - 1) (1 + (j - 1) (\delta - \mu + j \delta \mu)) ^ {n}. \end{array}\tag{5} \end{document} ]]></tex-math></disp-formula><p><italic>Proof</italic>. Suppose that</p><disp-formula id="equation-8"><tex-math id="math-48"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {j = 2} ^ {\infty} \phi (\alpha) | a _ {j} | \leq 2 (1 - \alpha) b, \end{document} ]]></tex-math></disp-formula><p>it is true for some <inline-formula><tex-math id="math-49"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b \in \mathbb { C } - \{ 0 \} , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } , \delta , \mu \geq 0 , 0 \leq \alpha < 1 \end{document} ]]></tex-math></inline-formula>, then it is suficient to prove that </p><disp-formula id="equation-9"><tex-math id="math-50"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| \frac {F (z) - 1}{F (z) + 1} \right| < 1. \end{document} ]]></tex-math></disp-formula><p>For <inline-formula><tex-math id="math-51"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula>, we define the function <inline-formula><tex-math id="math-52"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle F ( z ) \end{document} ]]></tex-math></inline-formula> by</p><disp-formula id="equation-10"><tex-math id="math-53"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle F (z) = 1 + \frac {1}{b} \left(\frac {R _ {\delta , \mu} ^ {m} f (z)}{R _ {\delta , \mu} ^ {n} f (z)} - 1\right) - \alpha ,\tag{6} \end{document} ]]></tex-math></disp-formula><p>which gives,</p><disp-formula id="equation-11"><tex-math id="math-54"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle F (z) - 1 = 1 + \frac {1}{b} \left(\frac {R _ {\delta , \mu} ^ {m} f (z)}{R _ {\delta , \mu} ^ {n} f (z)} - 1\right) - \alpha - 1\tag{7} \end{document} ]]></tex-math></disp-formula><p>and</p><disp-formula id="equation-12"><tex-math id="math-55"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle F (z) + 1 = 1 + \frac {1}{b} \left(\frac {R _ {\delta , \mu} ^ {m} f (z)}{R _ {\delta , \mu} ^ {n} f (z)} - 1\right) - \alpha + 1.\tag{8} \end{document} ]]></tex-math></disp-formula><p>From <xref ref-type="disp-formula" rid="equation-11">(7)</xref> and <xref ref-type="disp-formula" rid="equation-12">(8)</xref> we get,</p><disp-formula id="equation-13"><tex-math id="math-56"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{align*}\left| \frac{F(z) - 1}{F(z) + 1} \right| &= \left| \frac{\frac{\mathcal{R}_{\delta,\mu}^m f(z) - (1 + \alpha b) \mathcal{R}_{\delta,\mu}^n f(z)}{b \mathcal{R}_{\delta,\mu}^n f(z)}}{\frac{\mathcal{R}_{\delta,\mu}^m f(z) - [1 + (\alpha - 2)] \mathcal{R}_{\delta,\mu}^n f(z)}{b \mathcal{R}_{\delta,\mu}^n f(z)}} \right|, \\[1.5ex]\left| \frac{F(z) - 1}{F(z) + 1} \right| &= \left| \frac{\mathcal{R}_{\delta,\mu}^m f(z) - (1 + \alpha b) \mathcal{R}_{\delta,\mu}^n f(z)}{\mathcal{R}_{\delta,\mu}^m f(z) - [1 + (\alpha - 2)] \mathcal{R}_{\delta,\mu}^n f(z)} \right| \\[1.5ex]&= \left| \frac{\begin{array}{l} z + \sum_{j=2}^{\infty} [1 + (j - 1)(\delta - \mu + j\delta\mu)]^m a_j z^j \\ \quad - (1 + \alpha b)\left[ z + \sum_{j=2}^{\infty} [1 + (j - 1)(\delta - \mu + j\delta\mu)]^n a_j z^j \right] \end{array}}{\begin{array}{l} z + \sum_{j=2}^{\infty} [1 + (j - 1)(\delta - \mu + j\delta\mu)]^m a_j z^j \\ \quad - (1 + (\alpha - 2)b)\left[ z + \sum_{j=2}^{\infty} [1 + (j - 1)(\delta - \mu + j\delta\mu)]^n a_j z^j \right] \end{array}} \right|.\end{align*} \end{document} ]]></tex-math></disp-formula><p>We know that</p><disp-formula id="equation-14"><tex-math id="math-57"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| \frac {F (z) - 1}{F (z) + 1} \right| < 1, \end{document} ]]></tex-math></disp-formula><disp-formula id="equation-15"><tex-math id="math-58"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| \frac{%\begin{aligned}&-\alpha b z + \sum_{j=2}^{\infty} [1 + (j - 1)(\delta - \mu + j\delta\mu)]^m \\&- (1 + \alpha b) \sum_{j=2}^{\infty} [1 + (j - 1)(\delta - \mu + j\delta\mu)]^n a_j z z^{j-1}\end{aligned}%}{%\begin{aligned}&(2 - \alpha)b z + \sum_{j=2}^{\infty} [1 + (j - 1)(\delta - \mu + j\delta\mu)]^m \\&+ ((2 - \alpha)b - 1)[1 + (j - 1)(\delta - \mu + j\delta\mu)]^n a_j z z^{j-1}\end{aligned}%} \right| < 1, \end{document} ]]></tex-math></disp-formula><p>and</p><disp-formula id="equation-16"><tex-math id="math-59"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{align*}& \sum_{j=2}^{\infty} [1 + (j - 1)(\delta - \mu + j\delta\mu)]^m |a_j| \\& -(1 + \alpha b) \sum_{j=2}^{\infty} [1 + (j - 1)(\delta - \mu + j\delta\mu)]^n |a_j| \\& +\sum_{j=2}^{\infty} [1 + (j - 1)(\delta - \mu + j\delta\mu)]^m |a_j| \\& +((2 - \alpha)b - 1)[1 + (j - 1)(\delta - \mu + j\delta\mu)]^n |a_j| \le 2(1 - \alpha)b.\end{align*} \end{document} ]]></tex-math></disp-formula><p>Therefore,</p><disp-formula id="equation-17"><tex-math id="math-60"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {j = 2} ^ {\infty} \phi (\alpha) | a _ {j} | \leq 2 (1 - \alpha) b. \end{document} ]]></tex-math></disp-formula><p><inline-formula><tex-math id="math-61"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathrm { { L e t } = 0 } \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-62"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu = 0 \end{document} ]]></tex-math></inline-formula>, then the class <inline-formula><tex-math id="math-63"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> analogues the class <inline-formula><tex-math id="math-64"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula> was studied by Thirucheran and Stalin <xref ref-type="bibr" rid="BIBR-18">[18]</xref>.</p><p><bold>Corollary 2.3. </bold><italic>Let </italic><inline-formula><tex-math id="math-65"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> satisfies</italic></p><disp-formula id="equation-18"><tex-math id="math-66"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {j = 2} ^ {\infty} \phi (m, n, \alpha , \beta , \delta , b, j) | a _ {j} | \leq 2 (1 - \alpha) b,\tag{9} \end{document} ]]></tex-math></disp-formula><p>for some <inline-formula><tex-math id="math-67"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b \in \mathbb { C } - \left\{ 0 \right\} , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } , \delta , \mu \geq 0 , 0 \leq \alpha < 1 \end{document} ]]></tex-math></inline-formula>, then <inline-formula><tex-math id="math-68"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \in { \cal S } _ { b , m , n , \delta , } ( \alpha ) \end{document} ]]></tex-math></inline-formula>, where</p><disp-formula id="equation-19"><tex-math id="math-69"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array}{c} \phi (m, n, \alpha , \beta , \delta , b, j) = | (1 + (j - 1) \delta) ^ {m} - (1 + \alpha b) (1 + (j - 1) \delta) ^ {n} | \\ \qquad + (1 + (j - 1) \delta) ^ {m} + ((2 - \alpha) b - 1) (1 + (j - 1) \delta) ^ {n}. \end{array}\tag{10} \end{document} ]]></tex-math></disp-formula><p>Let <inline-formula><tex-math id="math-70"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b = 1 \end{document} ]]></tex-math></inline-formula> , then the class <inline-formula><tex-math id="math-71"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> reduces to</p><disp-formula id="equation-20"><tex-math id="math-72"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle R e \left(\frac {D _ {\delta} ^ {m} f (z)}{D _ {\delta} ^ {n} f (z)}\right) > \alpha , \end{document} ]]></tex-math></disp-formula><p>which analogue the class <inline-formula><tex-math id="math-73"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula> introduced by Sevtap Sumer Eker and Ozlem Guney<xref ref-type="bibr" rid="BIBR-20">[20]</xref>.</p><p><bold>Corollary 2.4. </bold><italic>Let </italic><inline-formula><tex-math id="math-74"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> satisfies the inequality</italic></p><disp-formula id="equation-21"><tex-math id="math-75"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {j = 2} ^ {\infty} \phi (\alpha , m, n, \delta , j) | a _ {j} | \leq 2 (1 - \alpha),\tag{11} \end{document} ]]></tex-math></disp-formula><p>for some <inline-formula><tex-math id="math-76"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle 0 \leq \alpha < 1 , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } , \delta , \geq 0 \end{document} ]]></tex-math></inline-formula>, then <inline-formula><tex-math id="math-77"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \in S _ { m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula>, </p><p>where</p><disp-formula id="equation-22"><tex-math id="math-78"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array}{c} \phi (\alpha , m, n, \delta , j) = | (1 + (j - 1) \delta) ^ {m} - (1 + \alpha) (1 + (j - 1) \delta) ^ {n} | \\ \qquad + (1 + (j - 1) \delta) ^ {m} + (1 - \alpha) (1 + (j - 1) \delta) ^ {n}. \end{array}\tag{12} \end{document} ]]></tex-math></disp-formula><p>If we put <inline-formula><tex-math id="math-79"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b = 1 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-80"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \delta = 1 \end{document} ]]></tex-math></inline-formula>, then the class <inline-formula><tex-math id="math-81"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> reduces to</p><disp-formula id="equation-23"><tex-math id="math-82"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle R e \left(\frac {D ^ {m} f (z)}{D ^ {n} f (z)}\right) > \alpha \end{document} ]]></tex-math></disp-formula><p>which analogues the class <inline-formula><tex-math id="math-83"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> introduced by Sevtap Sumer Eker and Owa <xref ref-type="bibr" rid="BIBR-19">[19]</xref>.</p><p><bold>Corollary 2.5.</bold><italic>Let </italic><inline-formula><tex-math id="math-84"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> satisfies</italic></p><disp-formula id="equation-24"><tex-math id="math-85"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {j = 2} ^ {\infty} \phi (\alpha , m, n, j) | a _ {j} | \leq 2 (1 - \alpha),\tag{13} \end{document} ]]></tex-math></disp-formula><p>for some <inline-formula><tex-math id="math-86"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \alpha ( 0 \leq \alpha < 1 ) , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } \end{document} ]]></tex-math></inline-formula>, then <inline-formula><tex-math id="math-87"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \in { \mathcal { S} } _ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula>, where </p><disp-formula id="equation-25"><tex-math id="math-88"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \phi (\alpha , m, n, j) = | (j) ^ {m} - (1 + \alpha) (j) ^ {n} | + (j) ^ {m} + (1 - \alpha) (j) ^ {n}.\tag{14} \end{document} ]]></tex-math></disp-formula><p>If <inline-formula><tex-math id="math-89"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b = 1 , m = n + 1 \end{document} ]]></tex-math></inline-formula>, and <inline-formula><tex-math id="math-90"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \delta = 1 \end{document} ]]></tex-math></inline-formula> , then the class <inline-formula><tex-math id="math-91"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula>, which reduces to the form</p><disp-formula id="equation-26"><tex-math id="math-92"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle R e \left(\frac {D ^ {n + 1} f (z)}{D ^ {n} f (z)}\right) > \alpha \end{document} ]]></tex-math></disp-formula><p>and analogues the class <inline-formula><tex-math id="math-93"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> introduced by Kadioglu <xref ref-type="bibr" rid="BIBR-21">[21]</xref>.</p><p><bold>Corollary 2.6. </bold><italic>Let </italic><inline-formula><tex-math id="math-94"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> satisfies the coefficient inequality</italic></p><disp-formula id="equation-27"><tex-math id="math-95"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {j = 2} ^ {\infty} (j ^ {n + 1} - \alpha j ^ {n}) | a _ {j} | \leq 1 - \alpha , \end{document} ]]></tex-math></disp-formula><p>for some <inline-formula><tex-math id="math-96"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle ( 0 \leq \alpha < 1 ) \end{document} ]]></tex-math></inline-formula>, then <inline-formula><tex-math id="math-97"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { S} } _ { n } ( \alpha ) \end{document} ]]></tex-math></inline-formula>.</p><p><bold>Theorem 2.7.</bold><italic>If </italic><inline-formula><tex-math id="math-98"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \in { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula><italic> for </italic><inline-formula><tex-math id="math-99"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle k \geq 2 \end{document} ]]></tex-math></inline-formula><italic>, then</italic></p><disp-formula id="equation-28"><tex-math id="math-100"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array}{c} \left| a _ {k} \right| \leq \frac {\beta}{\left| v _ {k} \right|} \left\{1 + \beta \sum_ {j = 2} ^ {k - 1} \frac {(1 + (j - 1) (\delta - \mu + j \delta \mu)) ^ {n}}{\left| v _ {j} \right|} \right. \\ + \beta^ {2} \sum_ {j _ {2} > j _ {1}} ^ {k - 1} \sum_ {j _ {1} = 2} ^ {k - 2} \frac {(1 + (j _ {1} - 1) (\delta - \mu + j _ {1} j \delta \mu + j _ {1})) (1 + (j _ {2} - 1) (\delta - \mu + j _ {2} j \delta \mu + j _ {2})) ^ {n}}{\left| v _ {j _ {1}} v _ {j _ {2}} \right|} \\ + \dots + \beta^ {k - 2} \prod_ {j = 2} ^ {k - 1} \frac {(1 + (j - 1) (\delta - \mu + j \delta \mu)) ^ {n}}{\left| v _ {j} \right|}, \end{array} \tag {15} \end{document} ]]></tex-math></disp-formula><p>Where </p><disp-formula id="equation-29"><tex-math id="math-101"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \beta = 2 (1 - \alpha) b \end{document} ]]></tex-math></disp-formula><p><italic>and</italic><inline-formula><tex-math id="math-102"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle v _ {k} = (1 + (j - 1) (\delta - \mu + j \delta \mu)) ^ {m} - (1 + (j - i) (\delta - \mu + j \delta \mu)) ^ {n}. \end{document} ]]></tex-math></inline-formula></p><p>If replace = 0 and <inline-formula><tex-math id="math-103"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu = 0 \end{document} ]]></tex-math></inline-formula> in <xref ref-type="disp-formula" rid="equation-28">(15)</xref>, then the class <inline-formula><tex-math id="math-104"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula>, reduces to the class <inline-formula><tex-math id="math-105"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \delta , \mu } ( \alpha ) \end{document} ]]></tex-math></inline-formula>, which is studied by Thirucheran and Stalin <xref ref-type="bibr" rid="BIBR-18">[18]</xref>.</p><p><bold>Corollary 2.8.</bold><italic>If </italic><inline-formula><tex-math id="math-106"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \in { \mathcal { S} } _ { b , m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula><italic> for </italic><inline-formula><tex-math id="math-107"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle k \geq 2 \end{document} ]]></tex-math></inline-formula><italic>, then</italic></p><disp-formula id="equation-30"><tex-math id="math-108"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{aligned}|a_k| \le \frac{\beta}{|v_k|} \Biggl\{ 1 &+ \beta \sum_{j=2}^{k-1} \frac{(1 + (j - 1)\delta)^n}{|v_j|} + \beta^2 \sum_{j_2 > j_1}^{k-1} \sum_{j_1=2}^{k-2} \frac{(1 + (j_1 - 1)\delta)(1 + (j_2 - 1)\delta)^n}{|v_{j_1} v_{j_2}|} \\&+ \dots + \beta^{k-2} \prod_{j=2}^{k-1} \frac{(1 + (j - 1)\delta)^n}{|v_j|} \Biggr\}, \quad (16)\end{aligned} \end{document} ]]></tex-math></disp-formula><p>where <inline-formula><tex-math id="math-109"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \beta = 2 ( 1 - \alpha ) b \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-110"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \boldsymbol { v } _ { k } = ( 1 + ( j - 1 ) \delta ) ^ { m } - ( 1 + ( j - i ) \delta ) ^ { n } \end{document} ]]></tex-math></inline-formula>.</p><p>If <inline-formula><tex-math id="math-111"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b = 1 \end{document} ]]></tex-math></inline-formula>, we get the results of subclass <inline-formula><tex-math id="math-112"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula> introduced by Sevtap Sumer Eker and Ozlem Guney <xref ref-type="bibr" rid="BIBR-20">[20]</xref>.</p><p><bold>Corollary 2.9. </bold><italic>If </italic><inline-formula><tex-math id="math-113"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \in { \mathcal { S} } _ { m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula><italic> for </italic><inline-formula><tex-math id="math-114"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle k \geq 2 \end{document} ]]></tex-math></inline-formula><italic> , then</italic></p><p><inline-formula><tex-math id="math-115"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{align*}|a_k| \le \frac{\beta}{|v_k|} \Biggl\{ 1 &+ \beta \sum_{j=2}^{k-1} \frac{(1 + (j - 1)\delta)^n}{|v_j|} + \beta^2 \sum_{j_2 > j_1}^{k-1} \sum_{j_1=2}^{k-2} \frac{(1 + (j_1 - 1)\delta)(1 + (j_2 - 1)\delta)^n}{|v_{j_1} v_{j_2}|} \\&+ \dots + \beta^{k-2} \prod_{j=2}^{k-1} \frac{(1 + (j - 1)\delta)^n}{|v_j|} \Biggr\}\end{align*} \end{document} ]]></tex-math></inline-formula></p><p>where <inline-formula><tex-math id="math-116"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \beta = 2 ( 1 - \alpha ) \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-117"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \boldsymbol { v } _ { k } = ( 1 + ( j - 1 ) \delta ) ^ { m } - ( 1 + ( j - i ) \delta ) ^ { n } \end{document} ]]></tex-math></inline-formula>.</p><p>If <inline-formula><tex-math id="math-118"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b = 1 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-119"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \delta = 1 \end{document} ]]></tex-math></inline-formula>, we get the result of the class <inline-formula><tex-math id="math-120"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> introduced by Sevtap Sumer Eker and Owa <xref ref-type="bibr" rid="BIBR-19">[19]</xref>.</p><p><bold>Corollary 2.10.</bold><italic>If </italic><inline-formula><tex-math id="math-121"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \in { \mathcal { S} } _ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula><italic> for </italic><inline-formula><tex-math id="math-122"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle k \geq 2 \end{document} ]]></tex-math></inline-formula><italic>, then</italic></p><disp-formula id="equation-31"><tex-math id="math-123"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| a _ {k} \right| \leq \frac {\beta}{\left| v _ {k} \right|} \left\{1 + \beta \sum_ {j = 2} ^ {k - 1} \frac {(j) ^ {n}}{\left| v _ {j} \right|} + \beta^ {2} \sum_ {j _ {2} > j _ {1}} ^ {k - 1} \sum_ {j _ {1} = 2} ^ {k - 2} \frac {\left(j _ {1} j _ {2}\right) ^ {n}}{\left| v _ {j _ {1}} v _ {j _ {2}} \right|} + \dots + \beta^ {k - 2} \prod_ {j = 2} ^ {k - 1} \frac {(j) ^ {n}}{\left| v _ {j} \right|}, \right. \end{document} ]]></tex-math></disp-formula><p>where <inline-formula><tex-math id="math-124"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \beta = 2 ( 1 - \alpha ) \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-125"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle v _ { k } = ( j ) ^ { m } - ( j ) ^ { n } \end{document} ]]></tex-math></inline-formula>.</p><p>Now we define the subclass <inline-formula><tex-math id="math-126"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \tilde { { \mathcal { S} } } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \subset { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula>, which consists of the function</p><disp-formula id="equation-32"><tex-math id="math-127"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f (z) = \sum_ {j = 2} ^ {\infty} a _ {j} z ^ {j}, (a _ {j} \geq 0).\tag{17} \end{document} ]]></tex-math></disp-formula><p>Now determine the extreme points for the subclass <inline-formula><tex-math id="math-128"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \tilde { { \mathcal { S} } } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula>.</p><p><bold>Theorem 2.11. </bold><italic>Let</italic></p><disp-formula id="equation-33"><tex-math id="math-129"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f _ {1} (z) = z, f _ {j} (z) = z + \sum_ {j = 2} ^ {\infty} \eta_ {j} \frac {2 (1 - \alpha) b}{\phi (\alpha)} z ^ {j}, (j = 2, 3, 4, \dots)\tag{18} \end{document} ]]></tex-math></disp-formula><p>then <inline-formula><tex-math id="math-130"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in \tilde { { \mathcal { S} } } _ { b , \delta , \mu } ^ { m , n } \end{document} ]]></tex-math></inline-formula> if and only if it can be expressed in the form <inline-formula><tex-math id="math-131"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array} { r } { f ( z ) = \sum _ { j = 1 } ^ { \infty } \eta _ { j } f _ { j } ( z ) } \end{array} \end{document} ]]></tex-math></inline-formula>, where <inline-formula><tex-math id="math-132"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta _ { j } > 0 \end{document} ]]></tex-math></inline-formula> and</p><disp-formula id="equation-34"><tex-math id="math-133"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {j = 1} ^ {\infty} \eta_ {j} = 1.\tag{19} \end{document} ]]></tex-math></disp-formula><p><italic>Proof</italic>. Suppose that</p><disp-formula id="equation-35"><tex-math id="math-134"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array}{l} f (z) = \sum_ {j = 1} ^ {\infty} \eta_ {j} f _ {j} (z) \\ \qquad = z + \sum_ {j = 2} ^ {\infty} \eta_ {j} \frac {2 (1 - \alpha) b}{\phi (\alpha)} z ^ {j} \\ \qquad = z + \sum_ {j = 2} ^ {\infty} \eta_ {j} \frac {2 (1 - \alpha) b}{\phi (\alpha)} \phi (\alpha) \\ \qquad = 2 (1 - \alpha) b \sum_ {j = 2} ^ {\infty} \eta_ {j} \\ \qquad = 2 (1 - \alpha) b (1 - \eta_ {1})  \end{array}\tag{20} \end{document} ]]></tex-math></disp-formula><disp-formula id="equation-36"><tex-math id="math-135"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \\ \qquad < 2 (1 - \alpha) b, \tag{21} \end{document} ]]></tex-math></disp-formula><p>which shows that <inline-formula><tex-math id="math-136"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \end{document} ]]></tex-math></inline-formula> satisfies the condition <xref ref-type="disp-formula" rid="equation-35">(20)</xref>. Hence, <inline-formula><tex-math id="math-137"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in \tilde { { \mathcal { S} } } _ { b , \delta , \mu } ^ { m , n } \end{document} ]]></tex-math></inline-formula>. Conversely, suppose that <inline-formula><tex-math id="math-138"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in \tilde { { \mathcal { S} } } _ { b , \delta , \mu } ^ { m , n } \end{document} ]]></tex-math></inline-formula> . Since,</p><disp-formula id="equation-37"><tex-math id="math-139"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle a _ {j} \leq \frac {2 (1 - \alpha) b}{\phi (\alpha)}, (j = 2, 3, \dots).\tag{22} \end{document} ]]></tex-math></disp-formula><p>Let</p><disp-formula id="equation-38"><tex-math id="math-140"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta_ {j} \leq \frac {\phi (\alpha)}{2 (1 - \alpha) b} a _ {j} \end{document} ]]></tex-math></disp-formula><p>and</p><disp-formula id="equation-39"><tex-math id="math-141"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta_ {1} = 1 - \sum_ {j = 2} ^ {\infty} \eta_ {j}, \end{document} ]]></tex-math></disp-formula><p>then we obtain</p><disp-formula id="equation-40"><tex-math id="math-142"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f (z) = \sum_ {j = 1} ^ {\infty} \eta_ {j} f _ {j} (z). \end{document} ]]></tex-math></disp-formula><p><inline-formula><tex-math id="math-143"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathrm { L e t } = 0 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-144"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu = 0 \end{document} ]]></tex-math></inline-formula> , then the class <inline-formula><tex-math id="math-145"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> reduces and analogues the class <inline-formula><tex-math id="math-146"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle S _ { b , m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula> studied by Thirucheran and Stalin <xref ref-type="bibr" rid="BIBR-18">[18]</xref>.</p><p><bold>Corollary 2.12. </bold><italic>Let</italic></p><disp-formula id="equation-41"><tex-math id="math-147"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f _ {1} (z) = z, f _ {j} (z) = z + \sum_ {j = 2} ^ {\infty} \eta_ {j} \frac {2 (1 - \alpha) b}{\phi (m , n , \alpha , \beta , \delta , b , j)} z ^ {j}, (j = 2, 3, 4, \dots)\tag{23} \end{document} ]]></tex-math></disp-formula><p>then <inline-formula><tex-math id="math-148"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in \tilde { { \mathcal { S} } } _ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> if and only if it can be expressed in the form <inline-formula><tex-math id="math-149"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array} { r } { f ( z ) = \sum _ { j = 1 } ^ { \infty } \eta _ { j } f _ { j } ( z ) } \end{array} \end{document} ]]></tex-math></inline-formula>, where <inline-formula><tex-math id="math-150"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta _ { j } > 0 \end{document} ]]></tex-math></inline-formula> and</p><disp-formula id="equation-42"><tex-math id="math-151"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {j = 1} ^ {\infty} \eta_ {j} = 1.\tag{24} \end{document} ]]></tex-math></disp-formula><p>Let <inline-formula><tex-math id="math-152"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b = 1 \end{document} ]]></tex-math></inline-formula>, we get the result of the class <inline-formula><tex-math id="math-153"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula> introduced by Sevtap Sumer Eker and Ozlem Guney <xref ref-type="bibr" rid="BIBR-20">[20]</xref>.</p><p><bold>Corollary 2.13. </bold><italic>Let </italic><inline-formula><tex-math id="math-154"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f _ { 1 } ( z ) = z \end{document} ]]></tex-math></inline-formula><italic> and</italic></p><disp-formula id="equation-43"><tex-math id="math-155"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f (z) = z + \frac {2 (1 - \alpha)}{\phi (\alpha , m , n , \delta , j)} z ^ {j}, \end{document} ]]></tex-math></disp-formula><p>then <inline-formula><tex-math id="math-156"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in \tilde { { \mathcal { S} } } _ { m , n , \delta } \end{document} ]]></tex-math></inline-formula> if and only if it can be expressed <inline-formula><tex-math id="math-157"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \textstyle \sum _ { j = 1 } ^ { \infty } \eta _ { j } f _ { j } ( z ) \end{document} ]]></tex-math></inline-formula>, where <inline-formula><tex-math id="math-158"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta _ { j } \mathrm { ~ > ~ } 0 , \textstyle \sum _ { j = 1 } ^ { \infty } \eta _ { j } = 1 \end{document} ]]></tex-math></inline-formula> .</p><p><bold>Theorem 2.14. </bold><italic>(Littlewood </italic><xref ref-type="bibr" rid="BIBR-23">[23]</xref><italic>) If </italic><inline-formula><tex-math id="math-159"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \end{document} ]]></tex-math></inline-formula><italic> and </italic><inline-formula><tex-math id="math-160"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle g \end{document} ]]></tex-math></inline-formula><italic> are analytic in </italic><inline-formula><tex-math id="math-161"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathbb { U } \end{document} ]]></tex-math></inline-formula><italic> with </italic><inline-formula><tex-math id="math-162"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \prec g ( z ) \end{document} ]]></tex-math></inline-formula><italic>, then</italic></p><disp-formula id="equation-44"><tex-math id="math-163"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \int_ {0} ^ {2 \pi} | f (z) | ^ {\mu} d \theta \leq \int_ {0} ^ {2 \pi} | g (z) | ^ {\mu} d \theta , \end{document} ]]></tex-math></disp-formula><p>for <inline-formula><tex-math id="math-164"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu > 0 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-165"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle z = r e ^ { i \theta } , 0 < r < 1 \end{document} ]]></tex-math></inline-formula>.</p><p><bold>Theorem 2.15. </bold><italic>Let </italic><inline-formula><tex-math id="math-166"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \cal S } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula><italic> and suppose that </italic><inline-formula><tex-math id="math-167"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f(z) \end{document} ]]></tex-math></inline-formula><italic> is defined by</italic></p><disp-formula id="equation-45"><tex-math id="math-168"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle g (z) = z + \frac {2 (1 - \alpha) b \varepsilon_ {j}}{\phi (\alpha)} z ^ {j}, (j = 2, 3, \dots), | \varepsilon_ {j} | = 1. \end{document} ]]></tex-math></disp-formula><p>If there exists an analytic function <inline-formula><tex-math id="math-169"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle w(z) \end{document} ]]></tex-math></inline-formula> given by</p><disp-formula id="equation-46"><tex-math id="math-170"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \{w (z) \} ^ {j - 1} = \frac {\phi (\alpha)}{2 (1 - \alpha) b \varepsilon_ {j}} \sum_ {j = 2} ^ {\infty} a _ {j} z ^ {j - 1}, z = r e ^ {i \theta}, 0 < r < 1, \end{document} ]]></tex-math></disp-formula><p>then</p><disp-formula id="equation-47"><tex-math id="math-171"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \int_ {0} ^ {2 \pi} \left| f (r e ^ {i \theta}) \right| ^ {\mu} d \theta \leq \int_ {0} ^ {2 \pi} \left| g (r e ^ {i \theta}) \right| ^ {\mu} d \theta , \mu > 0. \end{document} ]]></tex-math></disp-formula><p><italic>Proof</italic>. We must show that</p><disp-formula id="equation-48"><tex-math id="math-172"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \int_ {0} ^ {2 \pi} \left| 1 + \sum_ {j = 2} ^ {\infty} a _ {j} z ^ {j - 1} \right| ^ {\mu} d \theta \leq \int_ {0} ^ {2 \pi} \left| 1 + \frac {2 (1 - \alpha) b \varepsilon_ {j}}{\phi (\alpha)} z ^ {j - 1} \right| ^ {\mu} d \theta . \end{document} ]]></tex-math></disp-formula><p>By the help of Littlewood subordination theorem, it is suficient to show that</p><disp-formula id="equation-49"><tex-math id="math-173"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle 1 + \sum_ {j = 2} ^ {\infty} a _ {j} z ^ {j - 1} \prec 1 + \frac {2 (1 - \alpha) b \varepsilon_ {j}}{\phi (\alpha)} z ^ {j - 1}. \end{document} ]]></tex-math></disp-formula><p>Let</p><disp-formula id="equation-50"><tex-math id="math-174"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle 1 + \sum_ {j = 2} ^ {\infty} a _ {j} z ^ {j - 1} = 1 + \frac {2 (1 - \alpha) b \varepsilon_ {j}}{\phi (\alpha)} (w (z)) ^ {j - 1}). \end{document} ]]></tex-math></disp-formula><disp-formula id="equation-51"><tex-math id="math-175"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \therefore (w (z)) ^ {j - 1} = \frac {\phi (\alpha)}{2 (1 - \alpha) b \varepsilon_ {j}} \sum_ {j = 2} ^ {\infty} a _ {j} z ^ {j - 1}. \end{document} ]]></tex-math></disp-formula><p>Which readily yields <inline-formula><tex-math id="math-176"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle w ( 0 ) = 0 \end{document} ]]></tex-math></inline-formula>. Further, we prove that the analytic function <inline-formula><tex-math id="math-177"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle w ( z ) \end{document} ]]></tex-math></inline-formula> satisfies <inline-formula><tex-math id="math-178"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle | w ( z ) | < 1 \end{document} ]]></tex-math></inline-formula> using Schwarz lemma. We know that</p><disp-formula id="equation-52"><tex-math id="math-179"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| (w (z)) ^ {j - 1} \right| = \left| \frac {\phi (\alpha)}{2 (1 - \alpha) b \varepsilon_ {j}} \sum_ {j = 2} ^ {\infty} a _ {j} z ^ {j - 1} \right| \leq | z | < 1. \end{document} ]]></tex-math></disp-formula><p>Let <inline-formula><tex-math id="math-180"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle = 0 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-181"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu = 0 \end{document} ]]></tex-math></inline-formula>, then the class <inline-formula><tex-math id="math-182"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula> reduces to the class <inline-formula><tex-math id="math-183"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle S _ { b , m , n , \delta } ( \alpha ) \end{document} ]]></tex-math></inline-formula>，which is investigated by Thirucheran and Stalin <xref ref-type="bibr" rid="BIBR-18">[18]</xref>.</p><p><bold>Corollary 2.16. </bold><italic>Let </italic><inline-formula><tex-math id="math-184"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \cal S } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula><italic> and suppose that </italic><inline-formula><tex-math id="math-185"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \end{document} ]]></tex-math></inline-formula><italic> is defined by</italic></p><disp-formula id="equation-53"><tex-math id="math-186"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle g (z) = z + \frac {2 (1 - \alpha) b \varepsilon_ {j}}{\phi (m , n , \alpha , \beta , \delta , b , j)} z ^ {j}, (j = 2, 3, \dots), | \varepsilon_ {j} | = 1. \end{document} ]]></tex-math></disp-formula><p>If there exists an analytic function <inline-formula><tex-math id="math-187"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle w(z) \end{document} ]]></tex-math></inline-formula> given by</p><disp-formula id="equation-54"><tex-math id="math-188"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \{w (z) \} ^ {j - 1} = \frac {\phi (\alpha)}{2 (1 - \alpha) b \varepsilon_ {j}} \sum_ {j = 2} ^ {\infty} a _ {j} z ^ {j - 1}, z = r e ^ {i \theta}, 0 < r < 1, \end{document} ]]></tex-math></disp-formula><p>then</p><disp-formula id="equation-55"><tex-math id="math-189"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \int_ {0} ^ {2 \pi} \left| f (r e ^ {i \theta}) \right| ^ {\mu} d \theta \leq \int_ {0} ^ {2 \pi} \left| g (r e ^ {i \theta}) \right| ^ {\mu} d \theta , \mu > 0. \end{document} ]]></tex-math></disp-formula><p><bold>Definition 2.17. </bold><italic>Let </italic><inline-formula><tex-math id="math-190"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula><italic> denote the subclass of </italic><inline-formula><tex-math id="math-191"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> consisting of function </italic><inline-formula><tex-math id="math-192"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \end{document} ]]></tex-math></inline-formula><italic> which satisfies the inequality</italic></p><disp-formula id="equation-56"><tex-math id="math-193"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle R e \left(1 + \frac {1}{b} \left(\frac {R _ {\tau , \eta} ^ {m} f (z)}{R _ {\tau , \eta} ^ {n} f (z)} - 1\right)\right) > \mu \left| \frac {R _ {\tau , \eta} ^ {m} f (z)}{R _ {\tau , \eta} ^ {n} f (z)} - 1 \right| + \gamma .\tag{25} \end{document} ]]></tex-math></disp-formula><p>For some <inline-formula><tex-math id="math-194"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b \in \mathbb { C } - \left\{ 0 \right\} , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } , \mu , \tau , \eta \geq 0 , 0 \leq \gamma < 1 \end{document} ]]></tex-math></inline-formula> and all <inline-formula><tex-math id="math-195"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle z \in \mathbb { U } \end{document} ]]></tex-math></inline-formula>.</p><p>Several well known subclasses of functions are the special cases of <inline-formula><tex-math id="math-196"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula> for suitable choices of the parameters.</p><p>Remark 2.18. </p><list list-type="bullet"><list-item><p><inline-formula><tex-math id="math-197"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} }_ { b , 0 , 0 , \tau } ^ { m , n } ( \gamma ) { = } S ( m , n , \gamma , \mu , \tau , b , j ) \end{document} ]]></tex-math></inline-formula><italic> studied by Stalin and Thiruchran</italic><xref ref-type="bibr" rid="BIBR-24">[24]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-198"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { 1 , 0 , 0 , 1 } ^ { m , n } ( \gamma ) = K _ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula><italic>studied by Sumer Eker and Owa</italic><xref ref-type="bibr" rid="BIBR-19">[19]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-199"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { 1 , 0 , 0 , \tau } ^ { m , n } ( \gamma ) = S _ { m , n , \tau } ( \gamma ) \end{document} ]]></tex-math></inline-formula><italic>studied by Sumer Eker and Ozlem Guney</italic><xref ref-type="bibr" rid="BIBR-20">[20]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-200"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { 1 , 0 , 0 , 1 } ^ { n + 1 , n } ( \gamma ) = S _ { n } ( \gamma ) \end{document} ]]></tex-math></inline-formula><italic>studied by Kadioglu</italic><xref ref-type="bibr" rid="BIBR-21">[21]</xref>.</p></list-item></list><p><bold>Theorem 2.19. </bold><italic>Let </italic><inline-formula><tex-math id="math-201"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> satisfies</italic></p><disp-formula id="equation-57"><tex-math id="math-202"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {\nu = 2} ^ {\infty} \phi (\gamma , \mu) | a _ {\nu} | \leq 2 (1 - \gamma) b.\tag{26} \end{document} ]]></tex-math></disp-formula><p>For some <inline-formula><tex-math id="math-203"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b \in \mathbb { C } - \left\{ 0 \right\} , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } , \mu , \tau , \eta \geq 0 , 0 \leq \gamma < 1 \end{document} ]]></tex-math></inline-formula> and all <inline-formula><tex-math id="math-204"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle z \in \mathbb { U } \end{document} ]]></tex-math></inline-formula>, then <inline-formula><tex-math id="math-205"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { S} } _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula>, where</p><disp-formula id="equation-58"><tex-math id="math-206"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{equation*}\begin{aligned}\phi(\gamma,\mu)&=\left|(1+(\nu-1)(\tau-\eta+\nu\tau\eta))^{m}-(1+\gamma b)(1+(\nu-1)(\tau-\eta+\nu\tau\eta))^{n}\right|\\&\quad+(1+(\nu-1)(\tau-\eta+\nu\tau\eta))^{m}+((2-\gamma)b-1)(1+(\nu-1)(\tau-\eta+\nu\tau\eta))^{n}\\&\quad+2b\mu\left|(1+(\nu-1)(\tau-\eta+\nu\tau\eta))^{m}-(1+(\nu-1)(\tau-\eta+\nu\tau\eta))^{n}\right|.\end{aligned}\tag{27}\end{equation*} \end{document} ]]></tex-math></disp-formula><p><italic>Proof</italic>. Suppose that</p><disp-formula id="equation-59"><tex-math id="math-207"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {\nu = 2} ^ {\infty} \phi (\gamma , \mu) | a _ {\nu} | \leq 2 (1 - \gamma) b \end{document} ]]></tex-math></disp-formula><p>is true. For some <inline-formula><tex-math id="math-208"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b \in \mathbb { C } - \left\{ 0 \right\} , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } , \mu , \tau , \eta \geq 0 , 0 \leq \gamma < 1 \end{document} ]]></tex-math></inline-formula> and all <inline-formula><tex-math id="math-209"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle z \in \mathbb { U } \end{document} ]]></tex-math></inline-formula>, then it is suficient to prove that</p><disp-formula id="equation-60"><tex-math id="math-210"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| \frac {F (z) - 1}{F (z) + 1} \right| < 1. \end{document} ]]></tex-math></disp-formula><p>For <inline-formula><tex-math id="math-211"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula>, then define the function <inline-formula><tex-math id="math-212"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle F ( z ) \end{document} ]]></tex-math></inline-formula> by</p><disp-formula id="equation-61"><tex-math id="math-213"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle F (z) = 1 + \frac {1}{b} \left(\frac {R _ {\tau , \eta} ^ {m} f (z)}{R _ {\tau , \eta} ^ {n} f (z)} - 1\right) - \mu \left| \frac {R _ {\tau , \eta} ^ {m} f (z)}{R _ {\tau , \eta} ^ {n} f (z)} - 1 \right| - \gamma .\tag{28} \end{document} ]]></tex-math></disp-formula><p>Then</p><disp-formula id="equation-62"><tex-math id="math-214"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| \frac {F (z) - 1}{F (z) + 1} \right| = \left| \frac {R _ {\tau , \eta} ^ {m} f (z) - (1 + \gamma b) R _ {\tau , \eta} ^ {n} f (z) - b \mu \left| R _ {\tau , \eta} ^ {m} f (z) - R _ {\tau , \eta} ^ {n} f (z) \right|}{R _ {\tau , \eta} ^ {m} f (z) - (1 + (\gamma - 2) b) R _ {\tau , \eta} ^ {n} f (z) - b \mu \left| R _ {\tau , \eta} ^ {m} f (z) - R _ {\tau , \eta} ^ {n} f (z) \right|} \right| < 1, \end{document} ]]></tex-math></disp-formula><disp-formula id="equation-63"><tex-math id="math-215"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{aligned}\sum_{\nu=2}^{\infty} \Big\{ &\bigl| (1 + (\nu - 1)(\tau - \eta + \nu\tau\eta))^m - (1 + \gamma b)(1 + (\nu - 1)(\tau - \eta + \nu\tau\eta))^n \bigr| \\&+ \bigl( (1 + (\nu - 1)(\tau - \eta + \nu\tau\eta))^m + ((2 - \gamma)b - 1)(1 + (\nu - 1)(\tau - \eta + \nu\tau\eta))^n \bigr) \\&+ 2b\mu \bigl| (1 + (\nu - 1)(\tau - \eta + \nu\tau\eta))^m - (1 + (\nu - 1)(\tau - \eta + \nu\tau\eta))^n \bigr| \Big\} |a_\nu| \\&\le 2(1 - \gamma)b.\end{aligned} \end{document} ]]></tex-math></disp-formula><disp-formula id="equation-64"><tex-math id="math-216"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \therefore \sum_ {\nu = 2} ^ {\infty} \phi (\gamma , \mu) | a _ {\nu} | \leq 2 (1 - \gamma) b. \end{document} ]]></tex-math></disp-formula><p>Put <inline-formula><tex-math id="math-217"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu = 0 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-218"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta = 0 \end{document} ]]></tex-math></inline-formula> in <inline-formula><tex-math id="math-219"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \boldsymbol { { \mathcal { S} } } _ { b , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula>, then this class reduces as <inline-formula><tex-math id="math-220"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle S ( m , n , \gamma , \mu , \tau , b ) \end{document} ]]></tex-math></inline-formula>, which was studied by Thirucheran and Stalin <xref ref-type="bibr" rid="BIBR-24">[24]</xref>.</p><p><bold>Corollary 2.20. </bold><italic>Let </italic><inline-formula><tex-math id="math-221"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> satisfies</italic></p><disp-formula id="equation-65"><tex-math id="math-222"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {\nu = 2} ^ {\infty} \phi (m, n, \gamma , \mu , \tau , b, \nu) | a _ {\nu} | \leq 2 (1 - \gamma) b.\tag{29} \end{document} ]]></tex-math></disp-formula><p>For some <inline-formula><tex-math id="math-223"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle ( 0 \leq \gamma < 1 ) , \mu \geq 0 , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } , \tau ( \tau \geq 0 ) \end{document} ]]></tex-math></inline-formula>, and all <inline-formula><tex-math id="math-224"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle z \in \mathbb { U } \end{document} ]]></tex-math></inline-formula>, then <inline-formula><tex-math id="math-225"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in S ( m , n , \gamma , \mu , \tau , b ) \end{document} ]]></tex-math></inline-formula>, where</p><disp-formula id="equation-66"><tex-math id="math-226"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{equation*}\begin{aligned}\phi(m,n,\gamma,\mu,\tau,b,j)&=\left|(1+(\nu-1)\tau)^{m}-(1+\gamma b)(1+(\nu-1)\tau)^{n}\right|\\&\quad+(1+(\nu-1)\tau)^{m}+((2-\gamma)b-1)(1+(\nu-1)\tau)^{n}\\&\quad+2b\mu\left|(1+(\nu-1)\tau)^{m}-(1+(\nu-1)\tau)^{n}\right|.\end{aligned}\tag{30}\end{equation*} \end{document} ]]></tex-math></disp-formula><p>If <inline-formula><tex-math id="math-227"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b = 1 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-228"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu = 0 \end{document} ]]></tex-math></inline-formula>, then the class <inline-formula><tex-math id="math-229"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} }  _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula> reduces to</p><disp-formula id="equation-67"><tex-math id="math-230"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle R e \left(\frac {R _ {\tau , \eta} ^ {m} f (z)}{R _ {\tau , \eta} ^ {n} f (z)}\right) > \gamma \end{document} ]]></tex-math></disp-formula><p>which analogs to the class <inline-formula><tex-math id="math-231"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} }  _ { m , n , \tau } ( \gamma ) \end{document} ]]></tex-math></inline-formula> introduced by Sevtap Sumer Eker and Ozlem Guney<xref ref-type="bibr" rid="BIBR-20">[20]</xref>.</p><p><bold>Corollary 2.21. </bold><italic>Let </italic><inline-formula><tex-math id="math-232"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> satisfies the inequality</italic></p><disp-formula id="equation-68"><tex-math id="math-233"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {\nu = 2} ^ {\infty} \phi (\gamma , m, n, \tau , \nu) | a _ {\nu} | \leq 2 (1 - \gamma),\tag{31} \end{document} ]]></tex-math></disp-formula><p>for some <inline-formula><tex-math id="math-234"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b \in \mathbb { C } - \left\{ 0 \right\} , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } , \tau , \eta \geq 0 , 0 \leq \gamma < 1 \end{document} ]]></tex-math></inline-formula>, then <inline-formula><tex-math id="math-235"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \in { \mathcal { S} }  _ { m , n , \tau } ( \gamma ) \end{document} ]]></tex-math></inline-formula>， where</p><disp-formula id="equation-69"><tex-math id="math-236"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array}{c} \phi (\gamma , m, n, \tau , \nu) = | (1 + (\nu - 1) \tau) ^ {m} - (1 + \gamma) (1 + (\nu - 1) \tau) ^ {n} | \\ + (1 + (\nu - 1) \tau) ^ {m} + (1 - \gamma) (1 + (\nu - 1) \tau) ^ {n}. \end{array}\tag{32} \end{document} ]]></tex-math></disp-formula><p>If <inline-formula><tex-math id="math-237"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b = 1 , \mu = 0 \end{document} ]]></tex-math></inline-formula>, and <inline-formula><tex-math id="math-238"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \tau = 1 \end{document} ]]></tex-math></inline-formula>, then the class <inline-formula><tex-math id="math-239"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} }  _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula> given the class <inline-formula><tex-math id="math-240"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} }  _ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula>， which is discussed by Sevtap Sumer Eker and Owa <xref ref-type="bibr" rid="BIBR-19">[19]</xref></p><p><bold>Corollary 2.22. </bold><italic>Let </italic><inline-formula><tex-math id="math-241"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> satisfies</italic></p><disp-formula id="equation-70"><tex-math id="math-242"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {\nu = 2} ^ {\infty} \phi (\gamma , m, n, \nu) | a _ {\nu} | \leq 2 (1 - \gamma),\tag{33} \end{document} ]]></tex-math></disp-formula><p>for some <inline-formula><tex-math id="math-243"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \gamma ( 0 \leq \gamma < 1 ) , m \in \mathbb { N } , n \in \mathbb { N } _ { 0 } \end{document} ]]></tex-math></inline-formula>, then <inline-formula><tex-math id="math-244"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \ f ( z ) \in { \mathcal { S} }  _ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula>, where</p><disp-formula id="equation-71"><tex-math id="math-245"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \phi (\gamma , m, n, \nu) = | (j) ^ {m} - (1 + \gamma) (j) ^ {n} | + (j) ^ {m} + (1 - \gamma) (j) ^ {n}.\tag{34} \end{document} ]]></tex-math></disp-formula><p>We define the subclass <inline-formula><tex-math id="math-246"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \tilde { { \mathcal { S} } } _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \subset { \mathcal { S} } _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula>, which consists of the function</p><disp-formula id="equation-72"><tex-math id="math-247"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f (z) = z + \sum_ {\nu = 2} ^ {\infty} a _ {\nu} z ^ {\nu}, (a _ {\nu} \geq 0).\tag{35} \end{document} ]]></tex-math></disp-formula><p>Now we determine the extreme points of the subclass <inline-formula><tex-math id="math-248"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \tilde { { \mathcal { S} }} _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula>.</p><p><bold>Theorem 2.23.</bold><bold><italic></italic></bold><italic>Let </italic><inline-formula><tex-math id="math-249"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f _ { 1 } ( z ) = z \end{document} ]]></tex-math></inline-formula><italic> and</italic></p><disp-formula id="equation-73"><tex-math id="math-250"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f _ {\nu} (z) = z + \sum_ {\nu = 2} ^ {\infty} \vartheta_ {\nu} \frac {2 (1 - \gamma) b}{\phi (\gamma , \mu)} z ^ {\nu}, (\nu = 2, 3, 4, \dots),\tag{36} \end{document} ]]></tex-math></disp-formula><p>then <inline-formula><tex-math id="math-251"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in \tilde { { \mathcal { S} } } _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula> if and only if it can be expressed in the form</p><disp-formula id="equation-74"><tex-math id="math-252"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f (z) = \sum_ {\nu = 1} ^ {\infty} \vartheta_ {\nu} f _ {\nu} (z), \vartheta_ {\nu} > 0 \end{document} ]]></tex-math></disp-formula><p>and</p><disp-formula id="equation-75"><tex-math id="math-253"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {\nu = 1} ^ {\infty} \vartheta_ {\nu} = 1.\tag{37} \end{document} ]]></tex-math></disp-formula><p>Let <inline-formula><tex-math id="math-254"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle = 0 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-255"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta = 0 \end{document} ]]></tex-math></inline-formula>, then the class <inline-formula><tex-math id="math-256"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathcal { S } _ { b , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula> reduces and analogs the class, which is examined by Thirucheran and Stalin <xref ref-type="bibr" rid="BIBR-24">[24]</xref>.</p><p><bold>Corollary 2.24. </bold><italic>Let </italic><inline-formula><tex-math id="math-257"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f _ { 1 } ( z ) = z \end{document} ]]></tex-math></inline-formula><italic> and</italic></p><disp-formula id="equation-76"><tex-math id="math-258"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f _ {\nu} (z) = z + \sum_ {\nu = 2} ^ {\infty} \vartheta_ {\nu} \frac {2 (1 - \gamma) b}{\phi (m , n , \gamma , \mu , \tau , b , \nu)} z ^ {\nu}, (\nu = 2, 3, 4, \dots),\tag{38} \end{document} ]]></tex-math></disp-formula><p>then <inline-formula><tex-math id="math-259"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in \tilde { \mathcal { S } } ( m , n , \gamma , \mu , \tau , b ) \end{document} ]]></tex-math></inline-formula> if and only if it can be expressed in the form</p><disp-formula id="equation-77"><tex-math id="math-260"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f (z) = \sum_ {\nu = 1} ^ {\infty} \vartheta_ {\nu} f _ {\nu} (z), \vartheta_ {\nu} > 0 \end{document} ]]></tex-math></disp-formula><p>and</p><disp-formula id="equation-78"><tex-math id="math-261"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {\nu = 1} ^ {\infty} \vartheta_ {\nu} = 1.\tag{39} \end{document} ]]></tex-math></disp-formula><p>If <inline-formula><tex-math id="math-262"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle b = 1 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-263"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu = 0 \end{document} ]]></tex-math></inline-formula>, we get the result of the class <inline-formula><tex-math id="math-264"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S } } _ { m , n , \tau } ( \gamma ) \end{document} ]]></tex-math></inline-formula> introduced by Sevtap Sumer Eker and Ozlem Guney <xref ref-type="bibr" rid="BIBR-20">[20]</xref>.</p><p><bold>Corollary 2.25. </bold><italic>Let </italic><inline-formula><tex-math id="math-265"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f _ { 1 } ( z ) = z \end{document} ]]></tex-math></inline-formula><italic> and</italic></p><disp-formula id="equation-79"><tex-math id="math-266"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f (z) = z + \frac {2 (1 - \gamma)}{\phi (\gamma , m , n , \tau , \nu)} z ^ {\nu}, \end{document} ]]></tex-math></disp-formula><p>then <inline-formula><tex-math id="math-267"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in \tilde { { \mathcal { S} } } _ { m , n , \tau } \end{document} ]]></tex-math></inline-formula> if and only if it can be expressed</p><disp-formula id="equation-80"><tex-math id="math-268"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \sum_ {\nu = 1} ^ {\infty} \vartheta_ {\nu} f _ {\nu} (z), \vartheta_ {\nu} > 0. \end{document} ]]></tex-math></disp-formula><disp-formula id="equation-81"><tex-math id="math-269"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \therefore \sum_ {\nu = 1} ^ {\infty} \vartheta_ {\nu} = 1. \end{document} ]]></tex-math></disp-formula><p><bold>Theorem 2.26.</bold><bold><italic></italic></bold><italic>Let </italic><inline-formula><tex-math id="math-270"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \cal S } _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula><italic> and suppose that </italic><inline-formula><tex-math id="math-271"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \end{document} ]]></tex-math></inline-formula><italic> is defined by</italic></p><disp-formula id="equation-82"><tex-math id="math-272"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle g (z) = z + \frac {2 (1 - \gamma) b \varepsilon_ {\nu}}{\phi (\gamma , \mu)} z ^ {\nu}, (\nu = 2, 3, \dots), | \varepsilon_ {\nu} | = 1. \end{document} ]]></tex-math></disp-formula><p>If there exists an analytic function <inline-formula><tex-math id="math-273"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle w ( z ) \end{document} ]]></tex-math></inline-formula> given by</p><disp-formula id="equation-83"><tex-math id="math-274"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle (w (z)) ^ {\nu - 1} = \frac {\phi (\gamma , \mu)}{2 (1 - \gamma) b \varepsilon_ {\nu}} \sum_ {\nu = 2} ^ {\infty} a _ {\nu} z ^ {\nu - 1}, z = r e ^ {i \theta}, 0 < r < 1, \end{document} ]]></tex-math></disp-formula><p>then</p><disp-formula id="equation-84"><tex-math id="math-275"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \int_ {0} ^ {2 \pi} \left| f (r e ^ {i \theta}) \right| ^ {\eta} d \theta \leq \int_ {0} ^ {2 \pi} \left| g (r e ^ {i \theta}) \right| ^ {\eta} d \theta , \eta > 0. \end{document} ]]></tex-math></disp-formula><p><inline-formula><tex-math id="math-276"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathrm { L e t } = 0 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-277"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta = 0 \end{document} ]]></tex-math></inline-formula>, then the class <inline-formula><tex-math id="math-278"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathcal { S } _ { b , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula> reduces and analogs to the the class studied by Thirucheran and Stalin <xref ref-type="bibr" rid="BIBR-24">[24]</xref>.</p><p><bold>Corollary 2.27. </bold><italic>Let </italic><inline-formula><tex-math id="math-279"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in \mathcal { S } ( m , n , \gamma , \mu , \tau , b ) \end{document} ]]></tex-math></inline-formula><italic> and suppose that </italic><inline-formula><tex-math id="math-280"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \end{document} ]]></tex-math></inline-formula><italic> is defined by</italic></p><disp-formula id="equation-85"><tex-math id="math-281"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f (z) = z + \frac {2 (1 - \gamma) b \varepsilon_ {\nu}}{\phi (m , n , \gamma , \mu , \tau , b , \nu)} z ^ {\nu}, (\nu = 2, 3, \dots), | \varepsilon_ {\nu} | = 1. \end{document} ]]></tex-math></disp-formula><p>If there exists an analytic function <inline-formula><tex-math id="math-282"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle w(z) \end{document} ]]></tex-math></inline-formula> given by</p><disp-formula id="equation-86"><tex-math id="math-283"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle (w (z)) ^ {\nu - 1} = \frac {\phi (m , n , \gamma , \mu , \tau , b , \nu)}{2 (1 - \gamma) b \varepsilon_ {\nu}} \sum_ {\nu = 2} ^ {\infty} a _ {\nu} z ^ {\nu - 1}, z = r e ^ {i \theta}, 0 < r < 1, \end{document} ]]></tex-math></disp-formula><p>then</p><disp-formula id="equation-87"><tex-math id="math-284"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \int_ {0} ^ {2 \pi} \left| f (r e ^ {i \theta}) \right| ^ {\eta} d \theta \leq \int_ {0} ^ {2 \pi} \left| g (r e ^ {i \theta}) \right| ^ {\eta} d \theta , \eta > 0. \end{document} ]]></tex-math></disp-formula></sec><sec id="sec-4"><title>2.2. Fekete-Szego inequality for the subclasses { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) and { \mathcal { S} } _ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ).</title><p>In 1933, Fekete-Szego <xref ref-type="bibr" rid="BIBR-10">[10]</xref> obtained the maximum value of <inline-formula><tex-math id="math-285"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle | a _ { 3 } - \eta a _ { 2 } ^ { 2 } | \end{document} ]]></tex-math></inline-formula> as a function of the real parameter <inline-formula><tex-math id="math-286"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle η \end{document} ]]></tex-math></inline-formula>, for the function of class <inline-formula><tex-math id="math-287"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { A } } \end{document} ]]></tex-math></inline-formula>. Since then, the various authors were investigated and obtained the Fekete-Szego inequalities for diferent subclasses of the class $<inline-formula><tex-math id="math-288"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><xref ref-type="bibr" rid="BIBR-25">[25]</xref>, <xref ref-type="bibr" rid="BIBR-10">[10]</xref>, <xref ref-type="bibr" rid="BIBR-26">[26]</xref>, <xref ref-type="bibr" rid="BIBR-27">[27]</xref>, <xref ref-type="bibr" rid="BIBR-28">[28]</xref>, <xref ref-type="bibr" rid="BIBR-29">[29]</xref>, <xref ref-type="bibr" rid="BIBR-30">[30]</xref>, <xref ref-type="bibr" rid="BIBR-31">[31]</xref> .In this article, we introduced two new subclasses of univalent functions which are defined by using Raducanu-Ohran diferential operator in the open unit disc. For these subclasses, we obtain the Fekete-Szego inequality <inline-formula><tex-math id="math-289"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left|a_3-\eta a_2^2\right| \end{document} ]]></tex-math></inline-formula>.</p><p>If replacing special values for the subclass, we obtained Several well known subclasses.</p><p>Remark 2.28.</p><list list-type="bullet"><list-item><p><inline-formula><tex-math id="math-290"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { 1 , 0 , 1 , 0 } ^ { 1 , 0 } ( \alpha ) , { \mathcal { S} } _ { 1 , 0 , 0 , 1 , 0 } ^ { 1 , 0 } ( \alpha ) = { \mathcal { S} } ^ { \ast } ( \alpha ) \end{document} ]]></tex-math></inline-formula><italic>studied by W.Ma and D. Minda</italic><xref ref-type="bibr" rid="BIBR-32">[32]</xref></p></list-item><list-item><p><inline-formula><tex-math id="math-291"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , 0 , 1 , 0 } ^ { 1 , 0 } ( \alpha ) , { { \mathcal { S} } _ { b , 0 , 0 , 1 , 0 } ^ { 1 , 0 } } ( \alpha ) = { \mathcal { S} } _ { b } ^ { * } ( \alpha ) \end{document} ]]></tex-math></inline-formula><italic>studied by V. Ravichandran et.al.</italic><xref ref-type="bibr" rid="BIBR-27">[27]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-292"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , 0 , \delta , 0 } ^ { 2 , 0 } ( \alpha ) , \ { \mathcal { S} } _ { b , 0 , 0 , \delta , 0 } ^ { 2 , 0 } ( \alpha ) = \mathcal { M } _ { a , b } ( \phi ) \end{document} ]]></tex-math></inline-formula><italic> studied by K.Suchitra et.al. </italic><xref ref-type="bibr" rid="BIBR-29">[29]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-293"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} } _ { b , 0 , \delta , 0 } ^ { 2 , 1 } ( \alpha ) , \mathcal { S } _ { b , 0 , 0 , \delta , 0 } ^ { 2 , 1 } ( \alpha ) = \mathcal { M } _ { \alpha } ( \phi ) \end{document} ]]></tex-math></inline-formula><italic>studied by T.N.Shanmugam and S.Sivasubramanian</italic><xref ref-type="bibr" rid="BIBR-28">[28]</xref>.</p></list-item></list><p>Remark 2.29.</p><list list-type="bullet"><list-item><p><inline-formula><tex-math id="math-294"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} }   _ { 1 , 0 , 0 , 1 } ^ { 1 , 0 } ( \gamma ) = { \mathcal { S} }  ^ { * } ( \gamma ) \end{document} ]]></tex-math></inline-formula><italic>studied by W.Ma and D.Minda</italic><xref ref-type="bibr" rid="BIBR-32">[32]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-295"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} }  _ { b , 0 , 0 , 1 } ^ { 1 , 0 } ( \gamma ) = { \mathcal { S} }  _ { b } ^ { * } ( \gamma ) \end{document} ]]></tex-math></inline-formula><italic>studied by V. Ravichandran et.al.</italic><xref ref-type="bibr" rid="BIBR-27">[27]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-296"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} }  _ { b , 0 , 0 , \tau } ^ { 2 , 0 } ( \gamma ) = \mathcal { M } _ { a , b } ( \phi ) \end{document} ]]></tex-math></inline-formula><italic>studied by K.Suchitra et.al.</italic><xref ref-type="bibr" rid="BIBR-29">[29]</xref>.</p></list-item><list-item><p><inline-formula><tex-math id="math-297"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle { \mathcal { S} }  _ { b , 0 , 0 , \tau } ^ { 2 , 1 } ( \gamma ) = \mathcal { M } _ { \gamma } ( \phi ) \end{document} ]]></tex-math></inline-formula><italic>studied by T.N.Shanmugam and S.Sivasubramanian</italic><xref ref-type="bibr" rid="BIBR-28">[28]</xref>.</p></list-item></list><p><bold>Lemma 2.30. </bold><italic>If </italic><inline-formula><tex-math id="math-298"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle P ( z ) = 1 + c _ { 1 } z + c _ { 2 } z ^ { 2 } + c _ { 3 } z ^ { 3 } + . . \end{document} ]]></tex-math></inline-formula><italic> is a function with positive real part in </italic><inline-formula><tex-math id="math-299"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathbb { U } \end{document} ]]></tex-math></inline-formula><italic> and </italic><inline-formula><tex-math id="math-300"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle η \end{document} ]]></tex-math></inline-formula><italic> is a complex number, then</italic></p><disp-formula id="equation-88"><tex-math id="math-301"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| c _ {2} - \eta c _ {1} ^ {2} \right| \leq 2 M a x \{1, | 2 \eta - 1 | \}. \end{document} ]]></tex-math></disp-formula><p>The result is sharp for the function is given by <inline-formula><tex-math id="math-302"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \textstyle P ( z ) = { \frac { 1 + z ^ { 2 } } { 1 - z ^ { 2 } } } \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-303"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array} { r } { P ( z ) = \frac { 1 + z } { 1 - z } } \end{array} \end{document} ]]></tex-math></inline-formula>.</p><p><bold>Lemma 2.31. </bold><italic>If </italic><inline-formula><tex-math id="math-304"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle P ( z ) = 1 + c _ { 1 } z + c _ { 2 } z ^ { 2 } + c _ { 3 } z ^ { 3 } + . . . \end{document} ]]></tex-math></inline-formula><italic>. is a function with positive real part in </italic><inline-formula><tex-math id="math-305"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathbb { U } \end{document} ]]></tex-math></inline-formula><italic>, then</italic></p><p><inline-formula><tex-math id="math-306"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{equation*}\begin{aligned}\left|c_2-vc_1^2\right|\le\begin{cases}-4v+2, & v\le0,\\[0.5ex]2, & 0\le v\le1,\\[0.5ex]4v+2, & v\ge1.\end{cases}\end{aligned}\end{equation*} \end{document} ]]></tex-math></inline-formula></p><p>when <inline-formula><tex-math id="math-307"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle v < 0  \; or \; v  > 1 \end{document} ]]></tex-math></inline-formula>, the equality holds if and only if <inline-formula><tex-math id="math-308"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array} { r } { p _ { 1 } ( z ) = \frac { 1 + z } { 1 - z } } \end{array} \end{document} ]]></tex-math></inline-formula> or one of its rotations.</p><p>If <inline-formula><tex-math id="math-309"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathrm { ~ 0 ~ < ~ } v \mathrm { ~ < ~ } 1 \end{document} ]]></tex-math></inline-formula>, then the equality holds if and only if <inline-formula><tex-math id="math-310"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array} { r } {\ p _ { 1 } ( z ) = \frac { 1 + z ^ { 2 } } { 1 - z ^ { 2 } } } \end{array} \end{document} ]]></tex-math></inline-formula> or one of its rotations.</p><p>If <inline-formula><tex-math id="math-311"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle v = 0 \end{document} ]]></tex-math></inline-formula>, the equality holds if and only if<inline-formula><tex-math id="math-312"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array} { r } { p _ { 1 } ( z ) = \left( \frac { 1 } { 2 } + \frac { 1 } { 2 } \lambda \right) \frac { 1 + z } { 1 - z } + \left( \frac { 1 } { 2 } - \frac { 1 } { 2 } \lambda \right) \frac { 1 - z } { 1 + z } , ( 0 \leq } \lambda \leq 1 ) \end{array} \end{document} ]]></tex-math></inline-formula>  or one of its rotation.</p><p>If <inline-formula><tex-math id="math-313"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle v = 1 \end{document} ]]></tex-math></inline-formula>, the equality holds if and only if<inline-formula><tex-math id="math-314"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array} { r } { p _ { 1 } ( z ) = \left( \frac { 1 } { 2 } + \frac { 1 } { 2 } \lambda \right) \frac { 1 + z } { 1 - z } + \left( \frac { 1 } { 2 } - \frac { 1 } { 2 } \lambda \right) \frac { 1 - z } { 1 + z } , ( 0 \leq } \lambda \leq 1 ) \end{array} \end{document} ]]></tex-math></inline-formula>  is the reciprocal of one of the function such that equality holds in case of <inline-formula><tex-math id="math-315"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle v = 0 \end{document} ]]></tex-math></inline-formula>.</p><p>Also the above upper bound is sharp and it can be improved as follows: when  <inline-formula><tex-math id="math-316"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array} { r } { 0 < v < 1 \left| c _ { 2 } - v c _ { 1 } ^ { 2 } \right| + v | c _ { 1 } ^ { 2 } | \le 2 , 0 < v \le \frac { 1 } { 2 } \ a n d \left| c _ { 2 } - v c _ { 1 } ^ { 2 } \right| + ( 1 - v ) | c _ { 1 } ^ { 2 } | \le 2 , \frac { 1 } { 2 } < v < 1 . } \end{array} \end{document} ]]></tex-math></inline-formula></p><p><bold>Theorem 2.32. </bold><italic>Let </italic><inline-formula><tex-math id="math-317"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \phi ( z ) = 1 + B _ { 1 } z + B _ { 2 } z ^ { 2 } + B _ { 3 } z ^ { 3 } + . . . \end{document} ]]></tex-math></inline-formula><italic>, with </italic><inline-formula><tex-math id="math-318"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle B _ { 1 } \neq 0 \end{document} ]]></tex-math></inline-formula><italic>. </italic><inline-formula><tex-math id="math-319"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \ f \in { \mathcal { S} } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula><italic> satisfies the inequality</italic></p><disp-formula id="equation-89"><tex-math id="math-320"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle R e \left(1 + \frac {1}{b} \left(\frac {R _ {\delta , \mu} ^ {m} f (z)}{R _ {\delta , \mu} ^ {n} f (z)} - 1\right)\right) \prec \phi (z), \end{document} ]]></tex-math></disp-formula><p>then</p><disp-formula id="equation-90"><tex-math id="math-321"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array}{c} \left| a _ {3} - \mu_ {2} ^ {2} \right| \leq \frac {B _ {1} | b |}{[ (X _ {2}) ^ {m} - (X _ {2}) ^ {n} ]} \\ \times M a x \left\{1, \left| \frac {B _ {2}}{B _ {1}} + \left[ \frac {[ (X _ {1}) ^ {m + n} - (X _ {1}) ^ {2 n} ] - \mu [ (X _ {2}) ^ {m} - (X _ {2}) ^ {n} ]}{[ (X _ {1}) ^ {m} - (X _ {1}) ^ {n} ] ^ {2}} \right] b B _ {1} \right| \right\}, \end{array}\tag{40} \end{document} ]]></tex-math></disp-formula><p>where <inline-formula><tex-math id="math-322"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle X _ { 1 } = 1 + \delta + 3 - \mu + 2 j \delta \mu \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-323"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle X _ { 2 } = 1 + \delta + 4 - \mu + 3 j \delta \mu . \end{document} ]]></tex-math></inline-formula></p><p>Then, the result is sharp.</p><p><italic>Proof</italic>. If <inline-formula><tex-math id="math-324"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \cal S } _ { b , \delta , \mu } ^ { m , n } ( \alpha ) \end{document} ]]></tex-math></inline-formula>, then there is a Schwarz function <inline-formula><tex-math id="math-325"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle w ( z ) \end{document} ]]></tex-math></inline-formula>, analytic in <inline-formula><tex-math id="math-326"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathbb { U } \end{document} ]]></tex-math></inline-formula> with <inline-formula><tex-math id="math-327"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle w ( 0 ) = 0 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-328"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle | w ( z ) | < 1 \end{document} ]]></tex-math></inline-formula> in <inline-formula><tex-math id="math-329"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathbb { U } \end{document} ]]></tex-math></inline-formula> such that</p><disp-formula id="equation-91"><tex-math id="math-330"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle 1 + \frac {1}{b} \left(\frac {R _ {\delta , \mu} ^ {m} f (z)}{R _ {\delta , \mu} ^ {n} f (z)} - 1\right) = \phi (w (z)).\tag{41} \end{document} ]]></tex-math></disp-formula><p>Define <inline-formula><tex-math id="math-331"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle P ( z ) \end{document} ]]></tex-math></inline-formula> by <inline-formula><tex-math id="math-332"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array} { r } { P ( z ) = \frac { 1 + w ( z ) } { 1 - w ( z ) } = 1 + c _ { 1 } z + c _ { 2 } z ^ { 2 } + c _ { 3 } z ^ { 3 } + . . . } \end{array} \end{document} ]]></tex-math></inline-formula></p><p>Since <inline-formula><tex-math id="math-333"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle w ( z ) \end{document} ]]></tex-math></inline-formula> is a Schwarz function, it is clear that <inline-formula><tex-math id="math-334"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle R e P ( z ) > 0 \end{document} ]]></tex-math></inline-formula> and <inline-formula><tex-math id="math-335"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle P ( 0 ) = 1 \end{document} ]]></tex-math></inline-formula>.</p><disp-formula id="equation-92"><tex-math id="math-336"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \therefore \phi (z) = \phi \left(\frac {P (z) - 1}{P (z) + 1}\right) = 1 + \frac {B _ {1} c _ {1}}{2} z + \left[ \frac {B _ {1}}{2} \left(c _ {2} - \frac {c _ {1} ^ {2}}{2} +\right) + \frac {B _ {2} c _ {1} ^ {2}}{4} \right] z ^ {2} + \dots \end{document} ]]></tex-math></disp-formula><p>Using Lemma (5.2.2), we get</p><disp-formula id="equation-93"><tex-math id="math-337"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle 1 + \frac {1}{b} \left(\frac {R _ {\delta , \mu} ^ {m} f (z)}{R _ {\delta , \mu} ^ {n} f (z)} - 1\right) = 1 + \frac {B _ {1} c _ {1}}{2} z + \left[ \frac {B _ {1}}{2} \left(c _ {2} - \frac {c _ {1} ^ {2}}{2} +\right) + \frac {B _ {2} c _ {1} ^ {2}}{4} \right] z ^ {2} + \dots \end{document} ]]></tex-math></disp-formula><disp-formula id="equation-94"><tex-math id="math-338"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \therefore a _ {2} = \frac {b B _ {1} c _ {1}}{2 [ (X _ {1}) ^ {m} - (X _ {1}) ^ {n} ]} \end{document} ]]></tex-math></disp-formula><p>and</p><disp-formula id="equation-95"><tex-math id="math-339"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{aligned}a_3 &= \frac{b B_1 c_2}{2 [(X_2)^m - (X_2)^n]} \\&\quad + \frac{b B_1 c_1^2}{4 [(X_2)^m - (X_2)^n]} \left[ \frac{((X_1)^m - (X_1)^n)b B_1}{[(X_1)^m - (X_1)^n]^2} - \left(1 - \frac{B_2}{B_1}\right) \right] \\[8pt]\therefore a_3 - \mu a_2^2 &= \frac{b B_1}{2 [(X_2)^m - (X_2)^n]} \{c_2 - v c_1^2\},\end{aligned} \end{document} ]]></tex-math></disp-formula><p>where</p><disp-formula id="equation-96"><tex-math id="math-340"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle v = \frac {1}{2} \left(1 - \frac {B _ {2}}{B _ {1}} + \frac {\mu b B _ {1} \left[ (X _ {2}) ^ {m} - (X _ {2}) ^ {n} \right]}{\left[ (X _ {1}) ^ {m} - (X _ {1}) ^ {n} \right] ^ {2}} - \frac {b B _ {1} \left[ (X _ {1}) ^ {m + n} - (X _ {1}) ^ {2 n} \right]}{\left[ (X _ {1}) ^ {m} - (X _ {1}) ^ {n} \right] ^ {2}}\right). \end{document} ]]></tex-math></disp-formula><p>Hence</p><disp-formula id="equation-97"><tex-math id="math-341"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{aligned}|a_3 - \mu a_2^2| &\le \frac{B_1 |b|}{[(X_2)^m - (X_2)^n]} \\&\quad \times \max \Biggl\{ 1, \Biggl| \frac{B_2}{B_1} + \left[ \frac{[(X_1)^{m+n} - (X_1)^{2n}] - \mu [(X_2)^m - (X_2)^n]}{[(X_1)^m - (X_1)^n]^2} \right] b B_1 \Biggr| \Biggr\}.\end{aligned} \end{document} ]]></tex-math></disp-formula><p>Therefore, the result <xref ref-type="disp-formula" rid="equation-90">(40)</xref> is sharp for the function defined by</p><disp-formula id="equation-98"><tex-math id="math-342"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle 1 + \frac {1}{b} \left(\frac {R _ {\delta , \mu} ^ {m} f (z)}{R _ {\delta , \mu} ^ {n} f (z)} - 1\right) = \phi (z ^ {2}), 1 + \frac {1}{b} \left(\frac {R _ {\delta , \mu} ^ {m} f (z)}{R _ {\delta , \mu} ^ {n} f (z)} - 1\right) = \phi (z). \end{document} ]]></tex-math></disp-formula><p><bold>Theorem 2.33. </bold><italic>Let </italic><inline-formula><tex-math id="math-343"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \phi ( z ) = 1 + B _ { 1 } z + B _ { 2 } z ^ { 2 } + B _ { 3 } z ^ { 3 } + . . . , \end{document} ]]></tex-math></inline-formula><italic> with </italic><inline-formula><tex-math id="math-344"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle B _ { 1 } \neq 0 \end{document} ]]></tex-math></inline-formula><italic>. If </italic><inline-formula><tex-math id="math-345"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f \in { \mathcal { A } } \end{document} ]]></tex-math></inline-formula><italic> satisfies the inequality</italic></p><disp-formula id="equation-99"><tex-math id="math-346"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle R e \left(1 + \frac {1}{b} \left(\frac {R _ {\delta , \mu} ^ {m} f (z)}{R _ {\delta , \mu} ^ {n} f (z)} - 1\right)\right) \prec \phi (z), \end{document} ]]></tex-math></disp-formula><p>then</p><p><inline-formula><tex-math id="math-347"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{equation*}\begin{aligned}\left|a_2-\mu a_2^2\right|\le\begin{cases}A_1\left(-B_2-(1-2\mu A_2)A_3bB_1^2\right),& \mu\le\eta_1,\\[1ex]A_1,& \eta_1\le\mu\le\eta_2,\\[1ex]A_1\left(B_2+(1-2\mu A_2)A_3bB_1^2\right),& \mu\ge\eta_2.\end{cases}\end{aligned}\end{equation*} \end{document} ]]></tex-math></inline-formula></p><p>where</p><disp-formula id="equation-100"><tex-math id="math-348"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle A _ {1} = \frac {B _ {1} | b |}{2 [ (X _ {2}) ^ {m} - (X _ {2}) ^ {n} ]}, A _ {2} = \frac {(X _ {2}) ^ {m} - (X _ {2}) ^ {n}}{2 [ (X _ {2}) ^ {m + n} - (X _ {2}) ^ {2 n} ]}, A _ {3} = \frac {(X _ {1}) ^ {n}}{(X _ {1}) ^ {n} - (X _ {1}) ^ {m}}, \end{document} ]]></tex-math></disp-formula><disp-formula id="equation-101"><tex-math id="math-349"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta_ {1} = \frac {[ - (B _ {2} + B _ {1}) + A _ {3} b B _ {1} ^ {2} ] [ (X _ {1}) ^ {m} - (X _ {1}) ^ {n} ] ^ {2}}{[ (X _ {2}) ^ {n} - (X _ {1}) ^ {m} ] b B - 1 ^ {2}} \end{document} ]]></tex-math></disp-formula><p>and</p><disp-formula id="equation-102"><tex-math id="math-350"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta_ {2} = \frac {[ - (B _ {2} - B _ {1}) + A _ {3} b B _ {1} ^ {2} ] [ (X _ {1}) ^ {m} - (X _ {1}) ^ {n} ] ^ {2}}{[ (X _ {2}) ^ {n} - (X _ {1}) ^ {m} ] b B - 1 ^ {2}}. \end{document} ]]></tex-math></disp-formula><p><italic>Proof</italic>. Let <inline-formula><tex-math id="math-351"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu \leq \eta _ { 1 } \end{document} ]]></tex-math></inline-formula>, then</p><disp-formula id="equation-103"><tex-math id="math-352"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| a _ {2} - \mu a _ {2} ^ {2} \right| \leq A _ {1} \left(- B _ {2} - (1 - 2 \mu A _ {2}) A _ {3} b B _ {1} ^ {2}\right). \end{document} ]]></tex-math></disp-formula><p>Let <inline-formula><tex-math id="math-353"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta _ { 1 } \leq \mu \leq \eta _ { 2 } \end{document} ]]></tex-math></inline-formula>, then</p><disp-formula id="equation-104"><tex-math id="math-354"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle | a _ {2} - \mu a _ {2} ^ {2} | \leq A _ {1}. \end{document} ]]></tex-math></disp-formula><p>Let <inline-formula><tex-math id="math-355"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu \geq \eta _ { 2 } \end{document} ]]></tex-math></inline-formula>, then</p><disp-formula id="equation-105"><tex-math id="math-356"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| a _ {2} - \mu a _ {2} ^ {2} \right| \leq A _ {1} \left(B _ {2} + (1 - 2 \mu A _ {2}) A _ {3} b B _ {1} ^ {2}\right). \end{document} ]]></tex-math></disp-formula><p>To show that the bounds are sharp, for the functions <inline-formula><tex-math id="math-357"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle K _ { \phi , l } ( l \geq 2 ) \end{document} ]]></tex-math></inline-formula> well defined by</p><disp-formula id="equation-106"><tex-math id="math-358"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle 1 + \frac {1}{b} \left(\frac {\mathcal {D} ^ {m} K _ {\phi , l}}{\mathcal {D} ^ {n} K _ {\phi , l}} - 1\right) = \phi (z ^ {l - 1}), K _ {\phi , l} (0) = (K _ {\phi , l}) ^ {\prime} (0) - 1 = 0, \end{document} ]]></tex-math></disp-formula><p><inline-formula><tex-math id="math-359"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle F _ { \tau } , G _ { \tau } ( 0 \leq \tau \leq 1 ) \end{document} ]]></tex-math></inline-formula> well defined by</p><disp-formula id="equation-107"><tex-math id="math-360"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle 1 + \frac {1}{b} \left(\frac {\mathcal {D} ^ {m} F _ {\tau}}{\mathcal {D} ^ {n} F _ {\tau}} - 1\right) = \phi \left(\frac {z (z + (\delta - \mu + j \delta \mu))}{1 + (\delta - \mu + j \delta \mu) z}\right), F _ {\tau} (0) = (F _ {\tau}) ^ {\prime} (0) - 1 = 0 \end{document} ]]></tex-math></disp-formula><p>and</p><disp-formula id="equation-108"><tex-math id="math-361"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle 1 + \frac {1}{b} \left(\frac {\mathcal {D} ^ {m} G _ {\tau}}{\mathcal {D} ^ {n} G _ {\tau}} - 1\right) = \phi \left(- \frac {z (z + (\delta - \mu + j \delta \mu))}{1 + (\delta - \mu + j \delta \mu) z}\right), G _ {\tau} (0) = (G _ {\tau}) ^ {\prime} (0) - 1 = 0. \end{document} ]]></tex-math></disp-formula><p>It is clear that </p><disp-formula id="equation-109"><tex-math id="math-362"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle K _ {\phi , l} (l \geq 2), F _ {\tau}, G _ {\tau} (0 \leq \tau \leq 1) \end{document} ]]></tex-math></disp-formula><p> belongs to the class </p><disp-formula id="equation-110"><tex-math id="math-363"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathcal {S} _ {b, \delta , \mu} ^ {m, n} (\alpha) \end{document} ]]></tex-math></disp-formula><p>.</p><p>If <inline-formula><tex-math id="math-364"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu < \eta _ { 1 } \ \mathrm { o r } \ \mu > \end{document} ]]></tex-math></inline-formula><inline-formula><tex-math id="math-365"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle η_2 \end{document} ]]></tex-math></inline-formula>, then equality holds if and only if <inline-formula><tex-math id="math-366"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \end{document} ]]></tex-math></inline-formula> is <inline-formula><tex-math id="math-367"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle K _ { \phi , 2 } \end{document} ]]></tex-math></inline-formula> or one of its rotations. If <inline-formula><tex-math id="math-368"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \eta _ { 1 } < \mu < \eta _ { 2 } \end{document} ]]></tex-math></inline-formula>, then equality holds if and only if <inline-formula><tex-math id="math-369"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \end{document} ]]></tex-math></inline-formula> is <inline-formula><tex-math id="math-370"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle K _ { \phi , 3 } \end{document} ]]></tex-math></inline-formula> or one of its rotations. <inline-formula><tex-math id="math-371"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mathrm { ~ I f ~ } \mu = \eta _ { 1 } \end{document} ]]></tex-math></inline-formula>, then equality holds if and only if <inline-formula><tex-math id="math-372"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \end{document} ]]></tex-math></inline-formula> is <inline-formula><tex-math id="math-373"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle F _ { \tau } \end{document} ]]></tex-math></inline-formula> or one of its rotations. If <inline-formula><tex-math id="math-374"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \mu = \eta _ { 2 } \end{document} ]]></tex-math></inline-formula>, then equality holds if and only if <inline-formula><tex-math id="math-375"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle f ( z ) \end{document} ]]></tex-math></inline-formula> is <inline-formula><tex-math id="math-376"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle G _ { \tau } \end{document} ]]></tex-math></inline-formula> or one of its rotations. </p><p><bold>Theorem 2.34. </bold><italic>let </italic><inline-formula><tex-math id="math-377"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \phi ( z ) = 1 + B _ { 1 } z + B _ { 2 } z ^ { 2 } + B _ { 3 } z ^ { 3 } + \dots \end{document} ]]></tex-math></inline-formula><italic>, with </italic><inline-formula><tex-math id="math-378"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle B _ { 1 } \neq 0 \end{document} ]]></tex-math></inline-formula><italic>. If </italic><inline-formula><tex-math id="math-379"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \ f \in {\mathcal {S }}_ { b , \mu , \tau , \eta } ^ { m , n } ( \gamma ) \end{document} ]]></tex-math></inline-formula><italic> satisfies the inequality</italic></p><disp-formula id="equation-111"><tex-math id="math-380"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle R e \left(1 + \frac {1}{b} \left(\frac {R _ {\tau , \eta} ^ {m} f (z)}{R _ {\tau , \eta} ^ {n} f (z)} - 1\right) - \mu \left| \frac {R _ {\tau , \eta} ^ {m} f (z)}{R _ {\tau , \eta} ^ {n} f (z)} - 1 \right|\right) \prec \phi (z), \end{document} ]]></tex-math></disp-formula><p>then</p><disp-formula id="equation-112"><tex-math id="math-381"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \left| a _ {3} - \eta_ {2} ^ {2} \right| \leq \frac {B _ {1} | b |}{Y _ {2} - b \mu | Y _ {2} |} m a x \left\{1, \left| \frac {B _ {2}}{B _ {1}} + \left[ \frac {[ Y _ {3} - b \mu | Y _ {3} | ] - \eta [ [ Y _ {2} ] - b \mu | Y _ {2} | ]}{[ Y _ {1} - b \mu [ Y _ {1} ] ] ^ {2}} \right] b B _ {1} \right| \right\},\tag{42} \end{document} ]]></tex-math></disp-formula><p>where</p><disp-formula id="equation-113"><tex-math id="math-382"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle \begin{array}{c} Y _ {1} = ((1 + (\tau - \eta + 2 \tau \eta))) ^ {m} - ((1 + (\tau - \eta + 2 \tau \eta))) ^ {n}, \\ Y _ {2} = ((1 + 2 (\tau - \eta + 3 \tau \eta))) ^ {m} - ((1 + 2 (\tau - \eta + 3 \tau \eta))) ^ {n}, \end{array} \end{document} ]]></tex-math></disp-formula><p>and</p><disp-formula id="equation-114"><tex-math id="math-383"><![CDATA[ \documentclass{article} \usepackage{amsmath} \begin{document} \displaystyle Y _ {3} = \left(\left(1 + (\tau - \eta + 2 \tau \eta)\right)\right) ^ {m + n} - \left(\left(1 + (\tau - \eta + 2 \tau \eta)\right)\right) ^ {2 n}. \end{document} ]]></tex-math></disp-formula><p>Then, the result is sharp.</p></sec></sec><sec id="sec-5"><title>3. CONCLUDING REMARKS</title><p>In this paper, we obtained several results for a new subclass of normalized analytic univalent functions and compared them with existing results in the literature. The coeficient bounds for the proposed subclass were explicitly established. Moreover, by incorporating the R˘aducanu–Orhan operator, we extended the Fekete–Szeg¨o inequality to a broader class of holomorphic functions. The results provide new insights into the sharp bounds for the introduced subclass of univalent functions. Future work may explore applications of these findings in related areas such as geometric function theory and conformal mapping. 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