Integral transforms of functions to be in certain class defined by the combination of starlike and convex functions

被引:8
作者
Raghavendar, K. [1 ]
Swaminathan, A. [1 ]
机构
[1] Indian Inst Technol, Dept Math, Roorkee 247667, Uttar Pradesh, India
关键词
Pascu-class of a convex functions; Starlike functions; Convex functions; Integral transforms; Hypergeometric functions; ORDER;
D O I
10.1016/j.camwa.2011.12.077
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
Let P-gamma (beta). beta < 1, denote the class of all normalized analytic functions f in the unit disc D = {z epsilon C : |z| < 1} such that Re (e(i phi) ((1 - gamma)f(z)/z + gamma f' (Z) - beta)) > 0, z epsilon D for some phi epsilon R. Let M (mu,alpha), 0 <= mu < 1, denote the pascu class of alpha-convex functions of order mu and given by the analytic condition Re alpha z(zf'(z))' + (1-alpha)zf'(z)/alpha zf'(z) + (1-alpha)f(z) > mu which unifies S*(mu) and C(mu), respectively, the classes of analytic functions that map D onto the starlike and convex domain. In this work, we consider integral transforms of the form V-lambda(f)(z) = integral(1)(0) lambda(t) f(tz)/t dt. The aim of this paper is to find conditions on lambda(t) so that the above transformation carry P-gamma (beta) into M (mu, alpha). As applications, for specific values of lambda(t), it is found that several known integral operators carry P-gamma (beta) into M(mu, alpha). (C) 2012 Elsevier Ltd. All rights reserved.
引用
收藏
页码:1296 / 1304
页数:9
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