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

Yıl 2019, Cilt: 2 Sayı: 1, 9 - 12, 30.10.2019

Fethiye Müge Sakar , Seher Melike Aydoğan Şahsene Altınkaya

https://izlik.org/JA87EZ76ME

Öz

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.

Anahtar Kelimeler

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

Destekleyen Kurum

Batman University

Proje Numarası

BTUBAP2018-IIBF-2

Kaynakça

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