Sushil Kumar KUMAR, Asena ÇETİNKAYA

1815

Coefficient inequalities for certain starlike and convex functions

In this paper, we consider two Ma--Minda-type subclasses of starlike and convex functions associated with the normalized analytic function $\varphi_{Ne}(z)=1+z-z^3/3$ that maps an open unit disk onto the Nephroid shaped bounded domain in the right--half of the complex plane. We investigate convolution and quasi-Hadamard product properties for the functions belonging to such classes. In addition, we compute best possible estimates on third order Hermitian--Toeplitz determinant and non-sharp estimates on certain third order Hankel determinants for the starlike functions associated with the interior region of Nephroid.
Keywords:

Starlike functions, convex functions, Neproid, convolution properties quasi-Hadamard product properties, Hermitian--Toeplitz and Hankel determinants,

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Hacettepe Journal of Mathematics and Statistics-Cover
  • Yayın Aralığı: Yılda 6 Sayı
  • Başlangıç: 2002
  • Yayıncı: Hacettepe Üniversitesi Fen Fakultesi
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