SUBCLASS OF BAZILEVIC̆ AND λ-PSEUDO-STARLIKE BI-UNIVALENT FUNCTIONS ASSOCIATED WITH SAKAGUCHI TYPE FUNCTIONS AND ITS APPLICATION TO FIBONACCI-LIKE POLYNOMIAL

Year 2025, Volume: 26 Issue: 3, 217 - 230, 25.09.2025

Hasan Hüseyin Güleç , İbrahim Aktaş

https://doi.org/10.18038/estubtda.1665080

Abstract

In this paper, we first introduce a new subclass of analytic and bi-univalent functions related to Sakaguchi type functions, λ-pseudo-starlike and, Bazilevič functions. We also use the generalized bivariate Fibonacci-like polynomial as a subordination function. In addition, we provide function examples to show that this class of functions is a non-empty set. We then establish bounds on certain coefficients of the Maclaurin series expansion of the functions belonging to this newly constructed subclass of bi-univalent functions. We also establish bounds on the Fekete-Szegö functional of the functions in the defined subclass. We note that the comprehensive function class in this work generalizes some previously studied function classes, and the results of this study re-establish certain results in the previously published papers

Keywords

Analytic function , Bazilevič functions , Bi-univalent function , Starlike functions , Fibonacci-like polynomial

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