Boundary Value Problems
Volume 2008 (2008), Article ID 742030, 11 pages
Research Article

Critical Point Theory Applied to a Class of the Systems of the Superquadratic Wave Equations

Tacksun Jung1 and Q-Heung Choi2

1Department of Mathematics, Kunsan National University, Kunsan 573-701, South Korea
2Department of Mathematics Education, Inha University, Incheon 402-751, South Korea

Received 22 July 2008; Accepted 25 December 2008

Academic Editor: Martin Schechter

Copyright © 2008 Tacksun Jung and Q-Heung Choi. 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.


We show the existence of a nontrivial solution for a class of the systems of the superquadratic nonlinear wave equations with Dirichlet boundary conditions and periodic conditions with a superquadratic nonlinear terms at infinity which have continuous derivatives. We approach the variational method and use the critical point theory which is the Linking Theorem for the strongly indefinite corresponding functional.