On starlikeness of certain integral transforms

On Certain Sufficient Conditions for Starlikeness

We consider certain properties of f(z)f ′′(z)/f ′2(z) as a sufficient condition for starlikeness.

On starlikeness and close-to-convexity of certain analytic functions

Starlikeness Conditions for an Integral Operator

Let for fixed n ∈ N, Σn denotes the class of function of the following form f(z) = 1 z + ∞ ∑ k=n akz , which are analytic in the punctured open unit disk ∆∗ = {z ∈ C : 0 < |z| < 1}. In the present paper we defined and studied an operator in F (z) = [ c+ 1− μ zc+1 ∫ z 0 ( f(t) t )μ tdt ] 1 μ , for f ∈ Σn and c+ 1− μ > 0.

Starlikeness of Hadamard product of certain analytic functions

An interesting criterion was given by Lashin (A.Y. Lashin, Some convolution properties of analytic functions, Appl. Math. Lett. 18 (2005) 135–138) to be starlike for convolution of analytic functions f, g such that Re1⁄2f 0ðzÞ P a; Re1⁄2g0ðzÞ P b; a; b < 1 in the unit disc U. In this paper we shall improve this criterion. 2007 Elsevier Inc. All rights reserved.

Certain Conditions for Starlikeness of Analytic Functions of Koebe Type

For α ≥ 0, λ > 0, we consider theM α, λ b of normalized analytic α−λ convex functions defined in the open unit disc U. In this paper, we investigate the classM α, λ b, that is, Re{ zf ′ b z /fb z 1− α α 1 − λ zf ′ b z /fb z αλ 1 zf ′′ b z /f ′ b z } > 0, with fb is Koebe type, that is, fb z : z/ 1−zn . The subordination result for the aforementioned class will be given. Further, bymaking use of...