Advances in Difference Equations
Volume 2009 (2009), Article ID 618463, 11 pages
doi:10.1155/2009/618463
Research Article

On Approximate Cubic Homomorphisms

M. Eshaghi Gordji and M. Bavand Savadkouhi

Department of Mathematics, Semnan University, P. O. Box 35195-363, Semnan, Iran

Received 22 October 2008; Revised 4 March 2009; Accepted 2 July 2009

Academic Editor: Rigoberto Medina

Copyright © 2009 M. Eshaghi Gordji and M. Bavand Savadkouhi. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

We investigate the generalized Hyers-Ulam-Rassias stability of the system of functional equations: f(xy)=f(x)f(y), f(2x+y)+f(2x−y)=2f(x+y)+2f(x−y)+12f(x), on Banach algebras. Indeed we establish the superstability of this system by suitable control functions.