Schwarzian derivative and Janowski convexity

Nisha Bohra, V. Ravichandran

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.


Keywords


Schwarzian derivative; Janowski convexity; Subordination.

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References


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DOI: http://dx.doi.org/10.24193/subbmath.2017.2.06

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