ArticleOriginal scientific text

Title

On starlikeness of certain integral transforms

Authors 1

Affiliations

  1. 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 F(z)=0z(f(t)t)dt and G(z)=(2z)0zg(t)dt 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

Bibliography

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Pages:
227-232
Main language of publication
English
Received
1990-03-05
Published
1992
Exact and natural sciences