一类二阶非线性中立型泛函微分方程的周期解

摘要

利用重合度理论,研究二阶非线性中立型泛函微分方程[x（t）＋cx（t-（τ）]n＋f（x（t））x＇（t）＋g（x（t-σ））=p（t）的周期解的存在性,给出该方程存在周期解的充分性定理,并推广了已有的结果.%In this paper, we discuss the following nonlinear neutral delay equations. By using the coincidence degree theory, a sufficient condition for the existence of periodic solution of the equation is given, which generalizes the known result.