Inequalities for the Polar Derivative of a Polynomial

نویسندگان

  • M. Bidkham
  • M. Shakeri
  • M. Eshaghi Gordji
  • Narendra Kumar Govil
چکیده

In this paper we obtain new results concerning maximum modulus of the polar derivative of a polynomial with restricted zeros. Our results generalize and refine upon the results of Aziz and Shah [An integral mean estimate for polynomial, Indian J. Pure Appl. Math. 28 (1997) 1413–1419] and Gardner, Govil and Weems [Some result concerning rate of growth of polynomials, East J. Apporox. 10(2004) 301–312].

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تاریخ انتشار 2009