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

Recommended by Jong Kim

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.