Applications of higher-order q-derivatives to the subclass of q-starlike functions associated with the Janowski functions

Abstract

In this paper, we first investigate some subclasses of q-starlike functions. We then apply higher-order q-derivative operators to introduce and study a new subclass of q-starlike functions, which involves the Janowski functions. Several coefficient inequalities and a sufficient condition are derived. Relevant connections with a number of earlier works on this subject are also pointed out.

Keywords

• multivalent functions
• univalent functions
• convex and q-convex functions
• starlike and q-starlike functions
• q-derivative operator