Harmonic functions with varying coefficients

Springer Science and Business Media LLC - Tập 2016 - Trang 1-12 - 2016
Jacek Dziok1, Jay Jahangiri2, Herb Silverman3
1Faculty of Mathematics and Natural Sciences, University of Rzeszów, Rzeszów, Poland
2Department of Mathematical Sciences, Kent State University, Burton, USA
3Department of Mathematics, College of Charleston, Charleston, USA

Tóm tắt

Complex-valued harmonic functions that are univalent and sense preserving in the open unit disk can be written in the form $f=h+\overline{g}$ , where h and g are analytic. In this paper we investigate some classes of univalent harmonic functions with varying coefficients related to Janowski functions. By using the extreme points theory we obtain necessary and sufficient convolution conditions, coefficients estimates, distortion theorems, and integral mean inequalities for these classes of functions. The radii of starlikeness and convexity for these classes are also determined.

Tài liệu tham khảo

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