Closure properties of operators on the Ma-Minda type starlike and convex functions
نویسندگان
چکیده
A normalized univalent function f is called Ma–Minda starlike or convex if zf ðzÞ=f ðzÞ uðzÞ or 1þ zf ðzÞ=f 0ðzÞ uðzÞ where u is a convex univalent function with uð0Þ 1⁄4 1. The class of Ma–Minda convex functions is shown to be closed under certain operators that are generalizations of previously studied operators. Analogous inclusion results are also obtained for subclasses of starlike and close-to-convex functions. Connections with various earlier works are made. 2011 Elsevier Inc. All rights reserved.
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ورودعنوان ژورنال:
- Applied Mathematics and Computation
دوره 218 شماره
صفحات -
تاریخ انتشار 2011