Korean Journal of Mathematics

The Kangwon-Kyungki Mathematical Society (강원경기수학회)
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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)
  • Received : 2021.05.01
  • Accepted : 2021.09.10
  • Published : 2021.09.30
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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.

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References

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