### Coefficient Inequality for Transforms of Starlike and Convex Functions with Respect to Symmetric Points

KRISHNA, DEEKONDA VAMSHEE;VENKATESWARLU, BOLLINENI;RAMREDDY, THOUTREDDY

• 투고 : 2014.01.02
• 심사 : 2014.10.30
• 발행 : 2015.06.23
• 6 2

#### 초록

The objective of this paper is to obtain sharp upper bound for the second Hankel functional associated with the $k^{th}$ root transform $[f(z^k)]^{\frac{1}{k}}$ of normalized analytic function f(z) when it belongs to the class of starlike and convex functions with respect to symmetric points, defined on the open unit disc in the complex plane, using Toeplitz determinants.

#### 키워드

starlike and convex functions with respect to symmetric points;upper bound;second Hankel functional;positive real function;Toeplitz determinants

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