Department of Mathematics, Semnan University, P. O. Box 35195-363, Semnan, Iran
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.
We investigate the generalized Hyers-Ulam-Rassias stability of the system of functional equations:
, , on Banach algebras. Indeed we establish the superstability of this system by suitable control functions.