On generalized close-to-convexity related with strongly Janowski functions

Khalida Inayat Noor, Shujaat Ali Shah

Abstract


Janowski functions of strongly type are used to define certain classes of
analytic functions which generalize the concept of close-to-convexity and
bounded boundary rotation. Coefficient results, a necessary condition,
distortion bounds, Hankel determinant problem and several other interesting
properties of these classes are studied. Some significant well known results
are derived as special cases.


Keywords


Starlike; convex; bounded boundary rotation; Caratheodory and Janowski functions; subordination; convolution

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DOI: http://dx.doi.org/10.24193/subbmath.2023.4.09

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