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arXiv · 2203.16821

Necessary and Sufficient Condition for zeros of Derivative of Meromorphic and Entire Functions

ZhaoKun Ma·Lande Ma
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Abstract

The main result of this paper shows a totally new necessary and sufficient condition to determine both real and complex zeros of derivative of all entire and meromorphic functions of one complex variable in the extended complex plane. By using the theorem, we reprove some results about zeros of derivative of Xi function,Gamma function and digamma function in a new way.

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ZhaoKun Ma, Lande Ma. 2022-03-31. Necessary and Sufficient Condition for zeros of Derivative of Meromorphic and Entire Functions. https://arxiv.org/abs/2203.16821

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