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On the derivative and maximum modulus of a polynomial

Abstract

If is a polynomial of degree, having all its zeros in, then it was proved by Turán that. This result of Turán was generalized by Govil, who proved that if has all its zeros in,, then,. In this paper, we sharpen this, and some other related results.

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Correspondence to K. K. Dewan.

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Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License ( https://creativecommons.org/licenses/by/2.0 ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Dewan, K.K., Govil, N.K., Mir, A. et al. On the derivative and maximum modulus of a polynomial. J Inequal Appl 2006, 54816 (2006). https://doi.org/10.1155/JIA/2006/54816

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