Mathematics (May 2020)

Starlikeness Condition for a New Differential-Integral Operator

  • Mugur Acu,
  • Gheorghe Oros

DOI
https://doi.org/10.3390/math8050694
Journal volume & issue
Vol. 8, no. 5
p. 694

Abstract

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A new differential-integral operator of the form I n f ( z ) = ( 1 − λ ) S n f ( z ) + λ L n f ( z ) , z ∈ U , f ∈ A , 0 ≤ λ ≤ 1 , n ∈ N is introduced in this paper, where S n is the Sălăgean differential operator and L n is the Alexander integral operator. Using this operator, a new integral operator is defined as: F ( z ) = β + γ z γ ∫ 0 z I n f ( z ) · t β + γ − 2 d t 1 β , where I n f ( z ) is the differential-integral operator given above. Using a differential subordination, we prove that the integral operator F ( z ) is starlike.

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