## Coefficient bounds for subclasses of bi-univalent functions defined by fractional derivative operator## S. S. Eker, B. Şeker, S. EceIn this paper, first we introduce new subclasses of analytic and bi-univalent functions defined by fractional derivative operator in the open unit disk and then for the functions belongs to these classes obtain upper bounds for the initial coefficients.Tbilisi Mathematical Journal, Vol. 13(3) (2020), pp. 1-10 |