ArticleOriginal scientific text

Title

Subclasses of typically real functions determined by some modular inequalities

Authors ,

Abstract

Let T be the family of all typically real functions, i.e. functions that are analytic in the unit disk Δ:={zC:|z|<1}, normalized by f(0)=f(0)1=0 and such that Im z Im f(z) 0 for zΔ. Moreover, let us denote: T(2):={fT:f(z)=f(z) for zΔ} and TM,g:={fT:fMg in Δ}, where M>1, gTS and S consists of all analytic functions, normalized and univalent in Δ.We investigate  classes in which the subordination is replaced with the majorization and the function g is typically real but does not necessarily univalent, i.e. classes {fT:fMg in Δ}, where M>1, gT, which we denote by TM,g. Furthermore, we broaden the class TM,g for the case M(0,1) in the following  way:TM,g={fT:|f(z)|M|g(z)| for zΔ}, gT.

Keywords

Typically real functions, majorization, subordination

Bibliography

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Main language of publication
English
Published
2010
Published online
2016-07-29
Exact and natural sciences