Abstract and Applied Analysis
Volume 2012 (2012), Article ID 307968, 14 pages
http://dx.doi.org/10.1155/2012/307968
Research Article

Existence of Positive Solutions of Neutral Differential Equations

B. Dorociaková, M. Kubjatková, and R. Olach

Department of Mathematics, University of Žilina, 010 26 Žilina, Slovakia

Received 10 November 2011; Accepted 14 December 2011

Academic Editor: Josef Diblík

Copyright © 2012 B. Dorociaková et al. 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

The paper contains some suffcient conditions for the existence of positive solutions which are bounded below and above by positive functions for the nonlinear neutral differential equations of higher order. These equations can also support the existence of positive solutions approaching zero at infinity.