The extension Chebyshev polynomial bounds for general subclasses of bi-univalent functions involving subordination

Ş. Altinkaya, F. M. Sakar, S. M. Aydoğan

In this present investigation, we use the trigonometric polynomials Un(q,eiθ) to get the initial coefficients of bi-univalent functions in the new-defined classes SΣ{a,b,c}(ξ,q,θ) and KΣ{a,b,c}(ξ,q,θ). We also derive Fekete-Szegö inequalities for functions in these classes. 

Tbilisi Mathematical Journal, Special Issue (8 - 2021), pp. 187-194