Initial coefficients of starlike functions with real coefficients

Document Type: Research Paper

Authors

1 Bharati Vidyapeeth's College of Engineering‎, ‎Delhi--110063‎, ‎India.

2 Department of Mathematics‎, ‎University of Delhi‎ ‎Delhi--110 007‎, ‎India.

3 Department of Mathematics‎, ‎University of Delhi‎, ‎Delhi--110 007‎, ‎India.

Abstract

The sharp bounds for the third and fourth coefficients of Ma-Minda starlike functions having fixed second coefficient are determined. These results are proved by using certain constraint coefficient problem for functions with positive real part whose coefficients are real and the first coefficient is kept fixed. Analogous results are obtained for a general class of close-to-convex functions

Keywords

Main Subjects


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Volume 43, Issue 6
November and December 2017
Pages 1837-1854
  • Receive Date: 12 May 2016
  • Revise Date: 26 October 2016
  • Accept Date: 26 October 2016