Inequalities for the S^th Derivative of Polynomials Not Vanishing inside A Circle

GULSHAN SINGH^1,

¹Govt. Department of Education Jammu and Kashmir, India

Cite this paper:
GULSHAN SINGH. Inequalities for the S^th Derivative of Polynomials Not Vanishing inside A Circle. American Journal of Mathematical Analysis. 2015; 3(1):1-4. doi: 10.12691/ajma-3-1-1

Abstract

Let P(z) be a polynomial of degree n having all its zeros in , then for , Bidkham and Dewan [J. Math. Anal. Appl. 166(1992), 191-193] proved max In this paper, we prove an interesting generalization as well as an improvement of this result by considering the s^th derivative of lacunary type of polynomials P(z) of degree n > 3.

Keywords:
derivative of a polynomial zeros exterior of circle lacunary inequalities

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