The subordination theorem for γ-µ-spiral-like functions of order λ

Abstract

In this paper, we introduce a novel subclass Sγ(λ, µ) of normalized analytic functions in the open unit disk U. First we obtain several sufficient conditions that a function belongs to the subclass Sγ(λ, µ). Furthermore, we derive the upper bounds for the initial Taylor-Maclaurin coefficients |a2|, |a3| and |a4| as well as the Fekete-Szegö type inequalities for functions belong to this subclass. The results presented in this paper would generalize and improve some recent works of several earlier authors.