Starlike Functions Based on Ruscheweyh <i>q</i>−Differential Operator defined in Janowski Domain

Abstract

In this paper, we make use of the concept of q−calculus in the theory of univalent functions, to obtain the bounds for certain coefficient functional problems of Janowski type starlike functions and to find the Fekete–Szegö functional. A similar results have been done for the function ℘−1. Further, for functions in newly defined class we determine coefficient estimates, distortion bounds, radius problems, results related to partial sums.

Keywords

• starlike functions
• convex functions
• subordination
• Fekete–Szegö inequality
• Hadamard product
• analytic functions