研究了三阶边值问题u(t)+f(t,u(t))=0,0〈t〈1,u(0)=u′(0)=u(1)=0的相伴正解,其中允许f(t,u)在t=0,t=1和u=0处奇异。通过考察非线性项f(t,u)在u=0和u=+∞处的增长特性并利用锥上的Guo-K rasnosel′skii不动点定理,证明了一个新的存在定理。
Twin positive solutions are studied for the third-order boundary value problem u(t)+f(t,u(t))=0,0t1,u(0)=u′(0)=u(1)=0,where f(t,u) is allowed to be singular at t=0,t=1 and u=0.By considering the growth features of the nonlinear term f(t,u) at u=0 and u=+∞and applying the Guo-Krasnosel′skii fixed point theorem on cone,a new existence theorem is proved.