First-order Schwartian derivative and some classes of univalent functions

Milutin Obradovic; Nikola Tuneski

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arXiv · 2606.03433

First-order Schwartian derivative and some classes of univalent functions

Milutin Obradovic·Nikola Tuneski

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Abstract

In this paper we give estimate of $|S'_{f}(0)|$, where $S_{f}(z)= \left(\frac{f''(z)}{f'(z)}\right)'-\frac{1}{2}\left(\frac{f''(z)}{f'(z)}\right)^{2}$ is the Schwartian derivative, and $f$ belongs to different classes of functions univalent in the open unit disc $\ID$.

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Milutin Obradovic, Nikola Tuneski. 2026-06-02. First-order Schwartian derivative and some classes of univalent functions. https://arxiv.org/abs/2606.03433

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