Third Hankel determinant for a certain subclass of analytic functions

Abstract

The third Hankel determinant H_3 (1) for subclass of analytic functions satisfying geometric condition Re (zf^' (z))/(f(z)) (〖f(z)〗^(α-1) f^' (z))/z^(α-1) >0 for nonnegative real number α in the open unit disk U={z∈ C:|z|<1} is derived in line with a method of classical analysis devised by Libera and Zlotkiewicz