ArticleOriginal scientific text
Title
On starlikeness of certain integral transforms
Authors 1
Affiliations
- Department of Mathematics, Indian Institute of Technology, Kanpur 208 016, India
Abstract
Let A denote the class of normalized analytic functions in the unit disc U = {z: |z| < 1}. The author obtains fixed values of δ and ϱ (δ ≈ 0.308390864..., ϱ ≈ 0.0903572...) such that the integral transforms F and G defined by
and
are starlike (univalent) in U, whenever f ∈ A and g ∈ A satisfy Ref'(z) > -δ and Re g'(z) > -ϱ respectively in U.
Keywords
subordination, convex function, starlike function, univalent function
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