DIFFERENTIAL SUBORDINATIONS USING RUSCHEWEYH DERIVATIVE AND SALAGEAN OPERATOR

Year 2014, Volume: 4 Issue: 1, 33 - 38, 01.06.2014

Alp Lupas Alina

Abstract

In the present paper we study the operator defined by using the Ruscheweyh derivative R mf z and the S˘al˘agean operator S mf z , denoted L m α : An → An, Lm α f z = 1−α R mf z +αSmf z , z ∈ U, where An = {f ∈ H U : f z = z+an+1z n+1+. . . , z ∈ U} is the class of normalized analytic functions. We obtain several differential subordinations regarding the operator L m α

Keywords

differential subordination, convex function, best dominant, differential operator, S˘al˘agean operator, Ruscheweyh derivative

References

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