Application of Gegenbauer polynomials for biunivalent functions defined by subordination

Abstract

We present and investigate a new subclass of biunivalent functions by applying Gegenbouer polynomials in this paper. Also, we find nonsharp estimates on the first two coefficients |b0| and |b1| for functions belonging to this subclass. Furthermore, the Fekete–Szegö inequality b1 − ηb20 for this subclass is obtained. We also point out some consequences of results.