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arXiv · 2208.01241

Radius Constants of Sigmoid Starlike Functions

Priyanka Goel·S. Sivaprasad Kumar
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Abstract

In the present investigation, we study the class of Sigmoid starlike functions, given by $\mathcal{S}^*_{SG}=\{f\in\mathcal{A}: {zf'(z)}/{f(z)}\prec 2/(1+e^{-z})\}$ in context of estimating the sharp radius constants associated with several known subclasses of starlike functions. Further, graphical validation for the sharpness of results is also provided.

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Priyanka Goel, S. Sivaprasad Kumar. 2022-08-02. Radius Constants of Sigmoid Starlike Functions. https://arxiv.org/abs/2208.01241

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