Coefficient estimates for a class of meromorphic bi-univalent functions

نویسندگان

  • Samaneh G. Hamidi
  • Suzeini A. Halim
  • Jay M. Jahangiri
چکیده

Article history: Received 23 April 2013 Accepted after revision 21 May 2013 Available online 30 May 2013 Presented by the Editorial Board Applying the Faber polynomial coefficient expansions to a class of meromorphic biunivalent functions, we obtain the general coefficient estimates for such functions and also examine their early coefficient bounds. A function univalent in the open unit disk is said to be bi-univalent if its inverse map is also univalent there. Both the technique and the coefficient bounds presented here are new on their own kind. We hope that this article will generate future interest in applying our approach to other related problems. © 2013 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved. r é s u m é Une fonction univalente dans le disque unité ouvert est dite bi-univalente si sa fonction inverse est aussi univalente dans ce domaine. Appliquant le développement à coefficients polynômes de Faber à cette classe de fonctions, nous obtenons des estimations du coefficient général de leur développement de Laurent. Nous examinons également les bornes pour leurs premiers coefficients. Les techniques et les bornes des coefficients présentées ici sont nouvelles dans leur genre. Nous espérons qu’elles susciteront un intérêt pour l’application de notre approche à des problèmes connexes. © 2013 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

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تاریخ انتشار 2013