Bi-Starlike and Bi-Convex Function Classes Connected to Shell-Like Curves and the q-Analogue of Fibonacci Numbers

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DOI: https://doi.org/10.28924/2291-8639-23-2025-201
Published: Aug 15, 2025
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Abdullah Alsoboh, Ala Amourah, Khaled Al Mashrafi, Tala Sasa, Bi-Starlike and Bi-Convex Function Classes Connected to Shell-Like Curves and the q-Analogue of Fibonacci Numbers, Int. J. Anal. Appl., 23 (2025), 201.

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Abdullah Alsoboh, Ala Amourah, Khaled Al Mashrafi, Tala Sasa

Abstract

Using the subordination principle, this study explores two subclasses of bi-univalent functions associated with shell-like curves via the q-analogue of Fibonacci numbers, namely the starlike and convex classes. We derive coefficient bounds for the initial terms of these function classes and establish the corresponding Fekete- Szegö inequalities. Our findings contribute to the advancement of biunivalent function theory and its interaction with special function spaces.

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