Generalizations of starlike harmonic functions defined  by Sălăgean and Ruscheweyh derivatives

Á. O.  Páll-Szabo

doi:10.37863/umzh.v74i10.6157

Á. O. Páll-Szabo Babes ̧-BolyaiUniv.,Cluj-Napoca,Romania https://orcid.org/0000-0003-3469-3362

DOI: https://doi.org/10.37863/umzh.v74i10.6157

Keywords: harmonic functions, Salagean and Ruscheweyh derivative, negative coefficients

Abstract

UDC 517.5

We investigate some generalizations of the classes of harmonic functions defined by the Sălăgean and Ruscheweyh derivatives. By using the extreme-points theory, we obtain the coefficient-estimates distortion theorems and mean integral inequalities for these classes of functions.

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