On the derivative and maximum modulus of a polynomial
© K.K. Dewan et al. 2006
Received: 2 October 2004
Accepted: 11 October 2005
Published: 6 February 2006
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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