一类Duffing型微分方程周期解的存在性

Existence of Periodic Solution for a Class of Duffing Differential Equation

本文研究二阶微分方程在周期一边界条件之下解的存在性．仅仅借助Ｌｅｒａｙ－Ｓｃｈａｕｄｅｒ的一个不动点定理，在允许ｇ（ｕ）超线性增长的情况下，我们得到了一个问题（１）（２）的周期解的存在性定理．

This paper deals with the existence of periodic solution of the second order differential equation of the form with periodic-boundary conditionOur result lie in that we permit g(u) to grow superlinearly in u and we only rely on Leray-Schauder's fixed point theorem.