Abstract：In this paper, the existence of solutions for a class of fully fourth-order boundary value problem $\begin{cases} u^{(4)}(t)=f(t,u(t),u'(t),u''(t),u'''(t)),t∈[0,1], \\ u(0)=u(1)=u''(0)=u''(1)=0 \end{cases}$ is discussed,where $f:[0,1]×R^{4}→R$ is a continuous function. Without restricting the growth condition of nonlinear terms and without assuming that they are non-negative in the general case, when $f(t,x_{0},x_{1},x{2},x_{3})$ satisfies the proper Nagumo-type condition on $x_{3}$, we obtain the existence of solutions for this equation via a truncating function and the lower and upper solution method.
陈雪春, 李永祥. 一类完全四阶边值问题解的存在性[J]. 浙江大学学报（理学版）, 2020, 47(2): 155-158.
CHEN Xuechun, LI Yongxiang. Existence of solutions for a class of fully fourth-order boundary value problems. Journal of ZheJIang University(Science Edition), 2020, 47(2): 155-158.
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2020, Vol. 47 
