Differential Sandwich Theorems with Generalised Derivative Operator

Abstract

In this paper, a generalized derivatives operator λ,βf introduced by the authors will be discussed. Some subordination and superordination results involving this operator for certain normalized analytic functions in the open unit disk will be investigated. Our results extend corresponding previously known results. Keywords—Analytic functions, Univalent functions, Derivative operator, Differential subordination, Differential superordination.