Geometric and Coefficient Estimates for Bi-Univalent Functions Defined Through Fibonacci Numbers

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DOI: https://doi.org/10.28924/2291-8639-24-2026-91
Published: Mar 19, 2026
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Omar Alnajar, Ala Amourah, Abdullah Alsoboh, Abed Al-Rahman M. Malkawi, Jamal Salah, Abdullrahman A. Al-Maqbali, Tala Sasa, Geometric and Coefficient Estimates for Bi-Univalent Functions Defined Through Fibonacci Numbers, Int. J. Anal. Appl., 24 (2026), 91.

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Omar Alnajar, Ala Amourah, Abdullah Alsoboh, Abed Al-Rahman M. Malkawi, Jamal Salah, Abdullrahman A. Al-Maqbali, Tala Sasa

Abstract

In this research work, the new subclass \(\mathbf{\Upsilon }_{\Sigma }^{\Im,\Game,\mathcal{L},m,\varphi }(\widetilde{q})\) of bi-univalent functions related to Fibonacci numbers is presented. Our primary contributions to this for functions in this particular subclass, the study entails placing restrictions on the absolute values of the second coefficient \(\left\vert a_{2}\right\vert\) and the third coefficient \(\left\vert a_{3}\right\vert\). Furthermore, Fekete-Szegö functional problems are solved by us. In addition, our analysis shows interesting results from the particular parameter values applied in our primary conclusions.

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