Liénard系统比较定理

Comparative Theorem of Liénard System

运用 Poincáre- Bendixson环域定理得到了 L iénard系统的两个比较定理 ,运用方程 x+f (x) x+g(x) =0的闭轨的存在性可以判定方程 x+f(x) x+g(x) h(x) =0及系统 x=φ(y) - F(x) ,y=- g(x)的闭轨的存在性。

In this paper the author uses the Poincráe Bendixson ring domain theorem to get two comparative theorems,using equation: +f(x)+g(x)=0, in the existence of closed orbits for equation: +f(x)+g(x)h()=0 and system =φ(y)-F(x), =-g(x) can be determined.