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THIRD HANKEL DETERMINANTS FOR STARLIKE AND CONVEX FUNCTIONS OF ORDER ALPHA

  • Orhan, Halit (Department of Mathematics Faculty of Science Ataturk University) ;
  • Zaprawa, Pawel (Department of Mathematics Lublin University of Technology)
  • Received : 2016.11.14
  • Accepted : 2017.05.23
  • Published : 2018.01.31

Abstract

In this paper we obtain the bounds of the third Hankel determinants for the classes $\mathcal{S}^*({\alpha})$ of starlike functions of order ${\alpha}$ and $\mathcal{K}({\alpha}$) of convex functions of order ${\alpha}$. Moreover,we derive the sharp bounds for functions in these classes which are additionally 2-fold or 3-fold symmetric.

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