Abstract and Applied Analysis
Volume 2006 (2006), Article ID 10252, 9 pages
doi:10.1155/AAA/2006/10252
Multiple periodic solutions for a class of second-order nonlinear neutral delay equations
Xiao-Bao Shu1
and Yuan-Tong Xu2
1Department of Mathematics, Hunan University, Changsha 410082, China
2Department of Mathematics, Sun Yat-sen (Zhongshan) University, Guangzhou 510275, China
Abstract
By means of a variational structure and Z2-group index theory, we obtain multiple periodic solutions to a class of second-order nonlinear neutral delay equations of the formx″(t−τ)+λ(t)f(t,x(t),x(t−τ),x(t−2τ))=x(t),λ(t)>0,τ>0.