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  • Research Article
  • Open Access

On the derivative and maximum modulus of a polynomial

Journal of Inequalities and Applications20062006:54816

  • Received: 2 October 2004
  • Accepted: 11 October 2005
  • Published:


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.


  • Related Result
  • Maximum Modulus


Authors’ Affiliations

Department of Mathematics, Jamia Millia Islamia, New Delhi, 110025, India
Department of Mathematics, Auburn University, Auburn, AL 36849-5310, USA


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