Ukrainian Mathematical Journal

, Volume 70, Issue 8, pp 1288–1299 | Cite as

Sufficient Conditions for Bounded Turning of Analytic Functions

  • N. Tuneski
  • T. Bulboacă

Consider a function f analytic in the open unit disk and normalized so that f(0) = f′(0) 1 = 0. The methods of the theory of first-order differential subordinations are used to obtain sufficient conditions for the function f to have bounded turning, i.e., for the real part of its first derivative to map the unit disk onto the right half plane. In addition, several open problems are posed.


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • N. Tuneski
    • 1
  • T. Bulboacă
    • 2
  1. 1.Skopje Saints Cyril and Methodius UniversitySkopjeMacedonia
  2. 2.Babe¸s-Bolyai UniversityCluj-NapocaRomania

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