Mathematica Bohemica, first online, pp. 1-15


Coefficient bounds for the functions and inverse functions in the newly constructed subclass of bi-univalent functions

Gülizar Aşir, İbrahim Aktaş

Received May 7, 2025.   Published online October 27, 2025.

Abstract:  We introduce a novel subclass of bi-univalent functions with respect to symmetric points using generalized bivariate Fibonacci polynomials. Then we determine certain bounds for the initial coefficients of Maclaurin expansion of the functions belonging to this class of functions. In addition, we study the well-known Fekete-Szegö inequality for defined function class. We also discuss the same problems for the inverses of functions in this subclass. Further, we give a few corollaries for particular parameter values.
Keywords:  generalized bivariate Fibonacci polynomial; analytic function; bi-univalent function; coefficient estimate; Fekete-Szegö functional; coefficients of inverse function
Classification MSC:  30C45, 33C50

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Affiliations:   Gülizar Aşir, İbrahim Aktaş (corresponding author), Department of Mathematics, Kamil Özdağ Faculty of Science, Karamanoğlu Mehmetbey University, Yunus Emre Campus, 70100, Karaman, Turkey, e-mail: gulizarasir@kmu.edu.tr, ibrahimaktas@kmu.edu.tr, aktasibrahim38@gmail.com


 
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