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arXiv · 1908.01397

Notes on the norm of pre-Schwarzian derivatives on bi-univalent functions of order $\alpha$

H. Mahzoon·R. Kargar
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Abstract

In the present paper we estimate the norm of the pre-Schwarzian derivative of bi-starlike functions of order $\alpha$ where $\alpha\in[0,1)$. Initially this problem was handled by Rahmatan et al. in [Bull Iran Math Soc {\bf43}: 1037-1043, 2017]. We pointed out that the proofs and bounds by Rahmatan et al. are incorrect and present correct proofs and bounds.

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H. Mahzoon, R. Kargar. 2019-08-04. Notes on the norm of pre-Schwarzian derivatives on bi-univalent functions of order $\alpha$. https://arxiv.org/abs/1908.01397

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