Journal of Inequalities and Applications
Volume 2008 (2008), Article ID 195137, 8 pages
doi:10.1155/2008/195137
Research Article

Euler-Lagrange Type Cubic Operators and Their Norms on Xλ Space

Abbas Najati1 and Asghar Rahimi2

1Department of Mathematics, Faculty of Sciences, University of Mohaghegh Ardabil, P.O. Box 56199-11367 Ardabil, Iran
2Department of Mathematics, University of Maragheh, P.O. Box 55181-83111, Maragheh, East Azarbayjan, Iran

Received 17 April 2008; Accepted 1 July 2008

Academic Editor: Jong Kim

Copyright © 2008 Abbas Najati and Asghar Rahimi. 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 will introduce linear operators and obtain their exact norms defined on the function spaces Xλ and Zλ5. These operators are constructed from the Euler-Lagrange type cubic functional equations and their Pexider versions.