Advances in Difference Equations
Volume 2009 (2009), Article ID 826130, 17 pages
doi:10.1155/2009/826130
Research Article

Solution and Stability of a Mixed Type Additive, Quadratic, and Cubic Functional Equation

M. Eshaghi Gordji,1 S. Kaboli Gharetapeh,2 J. M. Rassias,3 and S. Zolfaghari1

1Department of Mathematics, Semnan University, P.O. Box 35195-363, Semnan, Iran
2Department of Mathematics, Payame Noor University of Mashhad, Mashhad, Iran
3Section of Mathematics and Informatics, Pedagogical Department, National and Capodistrian University of Athens, 4 Agamemnonos St., Aghia Paraskevi, Athens 15342, Greece

Received 24 January 2009; Revised 13 April 2009; Accepted 26 June 2009

Academic Editor: Patricia J. Y. Wong

Copyright © 2009 M. Eshaghi Gordji et al. 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 obtain the general solution and the generalized Hyers-Ulam-Rassias stability of the mixed type additive, quadratic, and cubic functional equation f(x+2y)−f(x−2y)=2(f(x+y)−f(x−y))+2f(3y)−6f(2y)+6f(y).