- Research Article
- Open Access
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.
- Harmonic Function
- Full Article
- Derivative Operator
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