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http://dx.doi.org/10.11568/kjm.2021.29.3.631

INEQUALITIES CONCERNING POLYNOMIAL AND ITS DERIVATIVE  

Zargar, B.A. (Department of Mathematics, University of Kashmir)
Gulzar, M.H. (Department of Mathematics, University of Kashmir)
Akhter, Tawheeda (Department of Mathematics, University of Kashmir)
Publication Information
Korean Journal of Mathematics / v.29, no.3, 2021 , pp. 631-638 More about this Journal
Abstract
In this paper, some sharp inequalities for ordinary derivative P'(z) and polar derivative DαP(z) = nP(z) + (α - z)P'(z) are obtained by including some of the coefficients and modulus of each individual zero of a polynomial P(z) of degree n not vanishing in the region |z| > k, k ≥ 1. Our results also improve the bounds of Turán's and Aziz's inequalities.
Keywords
Inequalities; polar derivative; modulus; coefficients;
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