Fixed Point Theory and Applications
Volume 2008 (2008), Article ID 732086, 11 pages
Research Article

A Fixed Point Approach to the Stability of Quadratic Functional Equation with Involution

Soon-Mo Jung1 and Zoon-Hee Lee2

1Mathematics Section, College of Science and Technology, Hong-Ik University, Chochiwon 339-701, South Korea
2Department of Mathematics, Chungnam National University, Deajeon 305-764, South Korea

Received 27 September 2007; Accepted 26 November 2007

Academic Editor: Tomas Domínguez Benavides

Copyright © 2008 Soon-Mo Jung and Zoon-Hee Lee. 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.


Cădariu and Radu applied the fixed point method to the investigation of Cauchy and Jensen functional equations. In this paper, we will adopt the idea of Cădariu and Radu to prove the Hyers-Ulam-Rassias stability of the quadratic functional equation with involution.