International Journal of Mathematics and Mathematical Sciences
Volume 2006 (2006), Issue 19, Pages 62548, 6 p.
doi:10.1155/IJMMS/2006/62548

Subordination by convex functions

Rosihan M. Ali , V. Ravichandran and N. Seenivasagan

School of Mathematical Sciences, Universiti Sains Malaysia (USM), Penang 11800, Malaysia

Abstract

For a fixed analytic function g(z)=z+n=2gnzn defined on the open unit disk and γ<1, let Tg(γ) denote the class of all analytic functions f(z)=z+n=2anzn satisfying n=2|angn|1γ. For functions in Tg(γ), a subordination result is derived involving the convolution with a normalized convex function. Our result includes as special cases several earlier works.