Journal of Inequalities and Applications
Volume 2008 (2008), Article ID 859105, 14 pages
A Class of Integral Operators Preserving Subordination and Superordination
Department of Applied Mathematics, Pukyong National University, Pusan 608-737, South Korea
Received 30 October 2007; Accepted 8 January 2008
Academic Editor: Donal O'Regan
Copyright © 2008 Nak Eun Cho and In Hwa Kim. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
We give some subordination- and superordination-preserving
properties of certain nonlinear integral operators defined on the space of normalized
analytic functions in the open unit disk. The sandwich-type theorems for these
integral operators are also obtained. Moreover, we consider an application of the
subordination and superordination theorems to the Gauss hypergeometric function.