Some Results of Differential Subordination and Differential Superordination Theorems for Univalent Functions Defined by Ruscheweyh Derivative Operator

Abstract

The purpose of the present paper is to derive several subordination, superordination results, and sandwich results for the function of the form $f\left(z\right)=z+\sum^{\infty }_{n=2}{a_nz^n}$ which is univalent in the open unit disc $\ U=\left\{z\in \mathbb{C}:\left|z\right|.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium provided the original work is properly cited.