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Growth of a polynomial with restricted zeros

  • Abdullah MirEmail author
  • Abrar Ahmad
  • Adil Hussain Malik
Original Research Paper
  • 3 Downloads

Abstract

In this paper, we establish some upper bound estimates for the maximal modulus of a polynomial on a disk \(|z|=R, \,R\ge 1\), when there is a restriction on its zeros. The obtained results generalize as well as sharpen some already known estimates due to Govil, Dalal and Govil, Dewan and Bhat and the classical result of Ankeny and Rivlin.

Keywords

Polynomial Maximum modulus Zeros 

Mathematics Subject Classification

30A10 30C10 30C15 

Notes

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Research involving human participants and/or animals

There was no research involving human participants and/or animals.

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Copyright information

© Forum D'Analystes, Chennai 2019

Authors and Affiliations

  • Abdullah Mir
    • 1
    Email author
  • Abrar Ahmad
    • 1
  • Adil Hussain Malik
    • 1
  1. 1.Department of MathematicsUniversity of KashmirSrinagarIndia

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