Complex analysis
Some properties related to a certain class of starlike functions
Comptes Rendus. Mathématique, Volume 353 (2015) no. 11, pp. 973-978

This paper considers a class Δ⁎ of normalized starlike functions f analytic in the open unit disk |z|<1 satisfying the inequality that

|{zf′(z)f(z)}2−1|<2|zf′(z)f(z)|
in |z|<1. We first show that the class S⁎(q) (defined below) is a subclass of Δ⁎ and then obtain some useful properties of these classes of functions.

Nous considérons dans cette Note une classe Δ⁎ de fonctions étoilées normalisées f, analytiques dans le disque unité ouvert |z|<1 et y satisfaisant l'inégalité

|{zf′(z)f(z)}2−1|<2|zf′(z)f(z)|.
Nous montrons d'abord que la classe S⁎(q) (définie ci-dessous) est une sous-classe de Δ⁎, puis nous obtenons quelques propriétés utiles de ces classes de fonctions.

Received:
Accepted:
Published online:
DOI: 10.1016/j.crma.2015.09.011

Ravinder Krishna Raina  1 ; Janusz Sokół  2

1 M.P. University of Agriculture and Technology, Udaipur, India
2 Department of Mathematics, Rzeszów University of Technology, al. Powstańców Warszawy 12, 35-959 Rzeszów, Poland
Ravinder Krishna Raina; Janusz Sokół. Some properties related to a certain class of starlike functions. Comptes Rendus. Mathématique, Volume 353 (2015) no. 11, pp. 973-978. doi: 10.1016/j.crma.2015.09.011
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