论文部分内容阅读
用Guo-Krasnoselskii不动点定理给出半正二阶离散周期边值问题Δ2u(t-1)+a(t)u(t)=λf(t,u(t)),t∈[1,T]Z,u(0)=u(T),Δu(0)=Δu(T{)正解的存在性和多解性结果,其中λ>0为参数,[1,T]Z={1,2,…,T},f:[1,T]Z×[0,∞)→R连续且存在常数D>0,使得f(t,u)≥-D,(t,u)∈[1,T]Z×[0,∞),