边值问题是一个在非线性泛函分析领域内被人们广泛研究的问题,有许多作者对边值问题进行了深刻的研究,但对于方程组边值问题的研究相对较少,本文利用锥上的不动点指数定理研究了如下具有特征值的二阶方程组边值问题: {(p1(t)u')'+λa(t)f(u(t),v(t))=0,0〈t〈1, (p2(t)v')'+μb(t)g(u(t),v(t))=0,0〈t〈1, u'(0)=u(1)=v(1)=v'(0)=0. 当λ,μ在某个范围内取值,f与g满足下面两个条件: (H1)f,g∈C[(R’×R’),[0,+∞)],a,b,p1,p2∈C((0,1),(0,∞)),min{f0,g0,f∞,g∞}≠0; (H2)存在H〉0,当0〈‖(u,v)‖≤H时,有‖f(u,v),g(u,v))‖〈N‖(u,v)‖,其中 N^-1=max{0∫0^11/p1(t)∫0^1a(s)dsdt,∫0^11/p2(t)∫0^1b(s)dsdt}〈+∞. 本文得到了两个正解的存在性,推广和改进了一些原有的结果.
The boundary value problems have been studied extensively, but the equations of them have been investigated scarcely. This paper researches the boundary value problems of some second-order equations having eigenvalue. {(p1(t)u')'+λa(t)f(u(t),v(t))=0,0〈t〈1, (p2(t)v')'+μb(t)g(u(t),v(t))=0,0〈t〈1, u'(0)=u(1)=v(1)=v'(0)=0. when λ and μ are small enough, the positive solutions are obtained by applying the theory of fixed point index under the following two conditions: (H1)f,g∈C[(R'×R'),[0,+∞)],a,b,p1,p2∈C((0,1),(0,∞)),min{f0,g0,f∞,g∞}≠0; (H2)There exists H〉0,and when 0〈 ‖ (u,v) ‖≤H,we have ‖ f(u,v),g(u,v)) ‖ 〈 N ‖ ( u, v) ‖ ,where N^-1=max{0∫0^11/p1(t)∫0^1a(s)dsdt,∫0^11/p2(t)∫0^1b(s)dsdt}〈+∞. The results of the paper partially improve the former relevant work.