On Harmonic Functions Defined by Derivative Operator
© K. Al-Shaqsi and M. Darus. 2008
Received: 16 September 2007
Accepted: 26 November 2007
Published: 3 December 2007
Let denote the class of functions that are harmonic univalent and sense-preserv- ing in the unit disk , where . In this paper, we introduce the class of functions which are harmonic in . A sufficient coefficient of this class is determined. It is shown that this coefficient bound is also necessary for the class if , where and . Coefficient conditions, such as distortion bounds, convolution conditions, convex combination, extreme points, and neighborhood for the class , are obtained.
To access the full article, please see PDF.
This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.