关于四阶和五阶非线性系统不稳定性的新结果

New Results About Instability of Some Fouth and Fifth Order Nonlinear Systems

本文运用Ｌｉａｐｕｎｏｖ 直接方法研究了一类四阶五阶非线性系统的不稳定性问题，解决了文［１］ 中遗留的问题，得到了较好的结果．文章最后给出了几个具体例子．

In this paper, we studied the instability of zero solution of a class of fourth and fifth order nonlinear differential equations by using Liapwnov direct method.Questions left over by paper(1) are solved and some better results are obstained.Meanwhile we gave several concrete examples at the last part of this paper.