In this paper we discuss about normalized holomorphic functions whose derivatives have positive real part. For this class of functions, denoted R, we present a general distortion result (some upper bounds for the modulus of the kth derivative of a function). We present also some remarks on the functions whose derivatives have positive real part of order α, α ∈ (0, 1). More details about these classes of functions can be found in [6], [8], [7, Chapter 4] and [4]. In the last part of this paper we present two new subclasses of normalized holomorphic functions whose derivatives have positive real part which generalize the classes R and R(α). For these classes we present some general results and examples.

## On some classes of holomorphic functions whose derivatives have positive real part

## Abstract

## Authors

Eduard Ștefan

**Grigoriciuc**Faculty of Mathematics and Computer Science, “Babeș-Bolyai” University, Cluj-Napoca, Romania

## Keywords

Univalent function, positive real part, distortion result, coefficient estimates

## Paper coordinates

E.S. Grigoriciuc, On some classes of holomorphic functions whose derivatives have positive real part,

*Stud. Univ. Babeș-Bolyai Math. 66 (2021), No. 3, 479-490*

## About this paper

##### Journal

Studia Mathematica

##### Publisher Name

Univ. Babes-Bolyai Math.

##### DOI

10.24193/subbmath.2021.3.06

##### Print ISSN

0252-1938

##### Online ISSN

2065-961x

## References

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