Coefficient Estimates for Certain Subclasses of Analytic Functions Defined by the q-Differential Operator
Keywords:
Geometric function theory, q-calculus, q-differential operator, analytic function, starlike function, coefficient estimatesAbstract
This paper aims to obtain coefficient estimates for a subclass of normalized analytic functions defined in the open unit disk by means of the q-differential operator. The considered class is characterized by a geometric condition related to a region that is starlike with respect to the point one and symmetric about the real axis. Using concepts from q-calculus and geometric function theory, several coefficient bounds are derived for functions belonging to this class. The obtained results extend and generalize a number of known findings in the theory of analytic and starlike functions. Furthermore, the corresponding results involving the classical derivative are recovered as a special limiting case when the parameter q approaches one from below.
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