International Journal of Mathematics and Mathematical Sciences
Volume 24 (2000), Issue 9, Pages 643-647
doi:10.1155/S0161171200004154

Some sufficient conditions for strongly starlikeness

Milutin Obradović1 and Shigeyoshi Owa2

1Department of Mathematics, Faculty of Technology and Metallurgy, 4 Karnegijova Street, Belgrade 11000, Serbia
2Department of Mathematics, Kinki University, Osaka, Higashi-Osaka 577-8502, Japan

Received 22 November 1999

Copyright © 2000 Milutin Obradović and Shigeyoshi Owa. 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.

Abstract

We consider strongly starlikeness of order α of functions f(z)=z+an+1zn+1+⋯ which are analytic in the unit disc and satisfy the condition of the form |f′(z)(zf(z))1+μ−1|<λ, 0<μ<1,  0<λ<1.