Polynomial Bounds for Bi-Univalent Functions Associated with Sigmoid Function and Q− Derivative Over a Chebyshev Polynomials
1 Department of Mathematical Sciences, Olusegun Agagu University of Science and Technology, Okitipupa, Ondo State, Nigeria
2 Department of Mathematics and Computing Science Education, Emmanuel Alayande University of Education, Oyo, P. M. B. 1010, Oyo, Nigeria
* Corresponding author: gbolagadeam@eauedoyo.edu.ng
2 Department of Mathematics and Computing Science Education, Emmanuel Alayande University of Education, Oyo, P. M. B. 1010, Oyo, Nigeria
* Corresponding author: gbolagadeam@eauedoyo.edu.ng
Abstract
This paper introduces a new subclass of the function class P of biunivalent analytic functions defined in the open unit disk, associated with a certain operator and the Sigmoid function via Chebyshev polynomials. Bounds for the initial coefficients are obtained
for the defined class, along with results for the Fekete–Szeg¨o functional. Furthermore, by varying the parameters involved, several
results are derived which extend existing findings in the literature.
Keywords
Chebyshev polynomial; Sigmoid Function; univalent functions; polynomial bounds; Fekete-Szego; q−operator.
How to Cite
Awolere, I. T., & Gbolagade, A. M. (2025). Polynomial Bounds for Bi-Univalent Functions Associated with Sigmoid Function and Q− Derivative Over a Chebyshev Polynomials. Nigerian Journal of Mathematics and Applications, 35(1), 71-81. https://doi.org/10.67897/njma.2025.bu0d8o9t
I. T. Awolere, and A. M. Gbolagade, "Polynomial Bounds for Bi-Univalent Functions Associated with Sigmoid Function and Q− Derivative Over a Chebyshev Polynomials," Nigerian Journal of Mathematics and Applications, vol. 35, no. 1, pp. 71-81, June 2025. doi: 10.67897/njma.2025.bu0d8o9t
