A new general subclass of analytic bi-univalent functions

A new general subclass of analytic bi-univalent functions

In a very recent work, Şeker [Seker B. On a new subclass of bi-univalent functions defined by usingSalagean operator. Turkish Journal of Mathematics 2018; 42: 2891–2896] defined two subclasses of analytic bi-univalentfunctions by means of Sălăgean differential operator and he obtained the initial Taylor–Maclaurin coefficient estimatesfor functions belonging to these classes. The main purpose of this paper is to improve the results obtained by Şeker inthe aforementioned study. For this purpose, we define a general subclass of bi-univalent functions.

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