Fekete‐Szegö Problems for Quasi‐Subordination Classes

An analytic function f is quasi‐subordinate to an analytic function g , in the open unit disk if there exist analytic functions φ and w , with | φ ( z )| ≤ 1, w (0) = 0 and | w ( z )| < 1 such that f ( z ) = φ ( z ) g ( w ( z )). Certain subclasses of analytic univalent functions associated with quasi‐subordination are defined and the bounds for the Fekete‐Szegö coefficient functional for functions belonging to these subclasses are derived.