Differential subordinations for fractional-linear transformations
Yong Chan Kim,1Adam Lecko,2Jae Ho Choi,3and Megumi Saigo3
Received29 May 1998
Revised29 Jun 1998
Abstract
We establish that the differential subordinations of the forms
p(z)+γzp′(z)≺h(A1,B1;z) or p(z)+γzp′(z)/p(z)≺h(A2,B2;z) implies p(z)≺h(A,B;z), where
γ≥0 and h(A,B;z)=(1+Az)/(1+Bz) with
−1≤B<A.