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Directional convexity of normalized harmonic convex mappings. (English) Zbl 1482.31006

Summary: In this paper, we prove that convolution of two half-plane harmonic mappings with suitable dilatation is convex in some particular direction. We also prove that convolution of slanted half-plane mappings and slanted strip mapping with fixed dilatation is convex in a particular direction. We give some examples for support of our results.

MSC:

31A05 Harmonic, subharmonic, superharmonic functions in two dimensions
30C45 Special classes of univalent and multivalent functions of one complex variable (starlike, convex, bounded rotation, etc.)
Full Text: DOI

References:

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