Differential subordination for Janowski functions with positive real part
DOI:
https://doi.org/10.24193/subbmath.2021.3.04Keywords:
Subordination, univalent functions, Carath´eodory functions, starlike functions, Janowski function, admissible function.Abstract
Theory of differential subordination provides techniques to reduce differential subordination problems into verifying some simple algebraic condition called admissibility condition. We exploit the first order differential subordination theory to get several sufficient conditions for function satisfying several differential subordinations to be a Janowski function with positive real part. As applications, we obtain sufficient conditions for normalized analytic functions to be Janowski starlike functions.
Mathematics Subject Classification (2010): 30C45.
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