Schwarzian derivative and Janowski convexity
DOI:
https://doi.org/10.24193/subbmath.2017.2.06Keywords:
Schwarzian derivative, Janowski convexity, Subordination.Abstract
Sufficient conditions relating the Schwarzian derivative to the Janowski convexity of a normalized analytic function f are obtained. As a consequence, sufficient conditions are determined for the function f to be Janowski convex and convex of order α. Also, some equivalent sharp inequalities are proved for f to be Janowski convex.
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