Mathematical analysis/Complex analysis
On some class of convex functions
[Sur une classe de fonctions convexes]

Présenté par : the Editorial Board

Sokół, Janusz1 ; Nunokawa, Mamoru2
1 Department of Mathematics, Rzeszów University of Technology, Al. Powstańców Warszawy 12, 35-959 Rzeszów, Poland
2 University of Gunma, Hoshikuki-cho 798-8, Chuou-Ward, Chiba, 260-0808, Japan
Comptes Rendus. Mathématique, Tome 353 (2015) no. 5, pp. 427-431.

Dans cette Note, nous considérons l'ordre d'étoilement et d'étoilement fort pour la classe de fonctions f(z)=z+a2z2+… , analytiques dans le disque unité {|z|<1} du plan complexe et satisfaisant

Re{1+zf″(z)f′(z)}>|zf′(z)f(z)−1|,|z|<1.

In this paper, we consider the order of starlikeness and strong starlikeness in the class of functions f(z)=z+a2z2+… analytic in |z|<1 in the complex plane and satisfying

Re{1+zf″(z)f′(z)}>|zf′(z)f(z)−1|,|z|<1.

Reçu le :
Accepté le :
Publié le :
DOI : 10.1016/j.crma.2015.03.002
Sokół, Janusz 1 ; Nunokawa, Mamoru 2

1 Department of Mathematics, Rzeszów University of Technology, Al. Powstańców Warszawy 12, 35-959 Rzeszów, Poland
2 University of Gunma, Hoshikuki-cho 798-8, Chuou-Ward, Chiba, 260-0808, Japan 
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Sokół, Janusz; Nunokawa, Mamoru. On some class of convex functions. Comptes Rendus. Mathématique, Tome 353 (2015) no. 5, pp. 427-431. doi : 10.1016/j.crma.2015.03.002. http://www.numdam.org/articles/10.1016/j.crma.2015.03.002/

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