Journal of Inequalities and Applications
Volume 2009 (2009), Article ID 892936, 17 pages
doi:10.1155/2009/892936
Research Article

Sufficient and Necessary Conditions for Oscillation of nth-Order Differential Equation with Retarded Argument

Jin-fa Cheng1 and Yu-ming Chu2

1Department of Mathematics, Xiamen University, Xiamen 361005, China
2Department of Mathematics, Huzhou Teachers College, Huzhou 313000, China

Received 10 July 2009; Revised 11 November 2009; Accepted 9 December 2009

Academic Editor: Martin Bohner

Copyright © 2009 Jin-fa Cheng and Yu-ming Chu. 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

Necessary and sufficient conditions are found for oscillation of the solutions of a class of strongly superlinear and strongly sublinear differential equations of even order with retarded argument.