First-Order Differential Subordinations for Janowski Starlikeness

  • Swati Anand
  • Sushil KumarEmail author
  • V. Ravichandran
Conference paper
Part of the Springer Proceedings in Mathematics & Statistics book series (PROMS, volume 306)


By using admissibility condition technique, certain sufficient conditions are determined so that an analytic function p defined on the open unit disk and normalized by \(p(0) = 1\) satisfy the subordination \(p(z) \prec (1+Az)/(1+Bz)\) whenever, for certain choice of \(\psi \), the function \(\psi (p(z), zp'(z))\) is subordinate to a starlike function associated with lune. Further, we obtain certain sufficient conditions for a normalized analytic function f to be in the class of Janowski starlike functions.


Differential subordination Admissibility condition Univalent functions Starlike functions Janowski starlike function Lune 


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© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  1. 1.Rajdhani College, University of DelhiDelhiIndia
  2. 2.Bharati Vidyapeeth’s College of EngineeringDelhiIndia
  3. 3.Department of MathematicsNational Institute of TechnologyTiruchirappalliIndia

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