Fekete–SzegÖ inequalities and initial coefficient bounds for Bi-univalent functions involving fractional q-differential operator subordination to q-hermite polynomials
Keywords:
q-Hermite Polynomials; Fekete–Szegö; Starlike; Fractional q-calculus; Convex functions.Abstract
In this paper, we introduce new subclasses of bi-univalent functions in the open unit disk defined via the q-fractional difference operator related to q-Hermite polynomials. Using subordination, we define the starlike class and the convex class . For functions in these classes, we derive upper bounds for the first two Taylor coefficients |a2| and |a3|, and we establish upper Fekete–Szegö inequalities for 2 aa 32 - b and 2 aa 32 - m , extending classical results to the q-fractional setting. We focus particularly on comparing the initial coefficients of these functions, providing insight into their geometric behavior and the influence of the q-fractional operator on the coefficient bounds.
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