Coefficient Bounds for a Subclass of $m$-fold Symmetric Bi-univalent Functions Involving Hadamard Product and Differential Operator

Year 2019, Volume: 2 Issue: 1, 9 - 12, 30.10.2019

Fethiye Müge Sakar , Seher Melike Aydoğan Şahsene Altınkaya

Abstract

In this study, we construct a new subclass of $m$-fold symmetric bi-univalent functions using by Hadamard product and generalized Salagean differential operator in the open unit disk $U=\left\{ z\in \mathbb{C} :\left\vert z\right\vert <1\right\} $. We establish upper bounds for the coefficients $\left\vert a_{m+1}\right\vert $ and $\left\vert a_{2m+1}\right\vert $ belonging to this new class. The results presented here generalize some of the earlier studies.

Keywords

Coefficient estimates, bi-univalent functions, m-fold symmetric functions

Supporting Institution

Batman University

Project Number

BTUBAP2018-IIBF-2

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