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Extremal Properties of Generalized Class of Close-to-convex Functions

Authors: Norlyda Mohamed, Daud Mohamad, Shaharuddin Cik Soh


Let Gα ,β (γ ,δ ) denote the class of function f (z), f (0) = f ′(0)−1= 0 which satisfied e δ {αf ′(z)+ βzf ′′(z)}> γ i Re in the open unit disk D = {z ∈ı : z < 1} for some α ∈ı (α ≠ 0) , β ∈ı and γ ∈ı (0 ≤γ <α ) where δ ≤ π and α cosδ −γ > 0 . In this paper, we determine some extremal properties including distortion theorem and argument of f ′( z ) .

Keywords: distortion theorem, Argument of f ′(z), Carathéodory Function, Closeto- convex Function, Extremal Properties

Digital Object Identifier (DOI):

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