Journal of Inequalities and Applications
Volume 2010 (2010), Article ID 167042, 12 pages
doi:10.1155/2010/167042
Research Article

Stability of a 2-Dimensional Functional Equation in a Class of Vector Variable Functions

Won-Gil Park1 and Jae-Hyeong Bae2

1Department of Mathematics Education, College of Education, Mokwon University, Daejeon 302-729, Republic of Korea
2College of Liberal Arts, Kyung Hee University, Yongin 449-701, Republic of Korea

Received 16 March 2010; Accepted 24 June 2010

Academic Editor: Patricia J. Y. Wong

Copyright © 2010 Won-Gil Park and Jae-Hyeong Bae. 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 prove the Hyers-Ulam stability of a 2-dimensional quadratic functional equation in a class of vector variable functions in Banach modules over a unital C⋆-algebra.