Zayed, H. M.Bulut, SerapMostafa, A. O.2021-11-032021-11-032019-02-01https://doi.org/10.31801/cfsuasmas.513114http://hdl.handle.net/20.500.12575/75872In this paper, we obtain Fekete-Szegö functional |a₁-μa₀²| for functions of the classes Σ_{q}^{∗}(ϕ) and Σ_{q,λ,b}^{∗}(g,ϕ) using quasi-subordination. Sharp bounds for the Fekete-Szegö functional |a₁-μa₀²| are obtained. Also, applications of the main results for subclasses of functions defined by Bessel function are also considered.enAnalyticMeromorphicStarlike functionArticle681119712052618-6470