摘要
研究了以三次代数曲线ｙ＝ａｘ３＋ｂｘ２＋ｃｘ＋ｄ为不变集的平面二次系统，进一步讨论了以ｙ＝ｘｎ（ｎ≥４）为不变集的平面二次系统，获得了此时无极限环的定论．
The quadratic system in plane with invariant set of cubic algebraic curve y=ax 3+bx 2+cx+d and y=x n(n≥4) is studied.It is proved that there is no limit cycle there.
出处
《烟台师范学院学报（自然科学版）》
1998年第1期4-6,18,共4页
Yantai Teachers University journal(Natural Science Edition)
关键词
不变集
平面二次系统
极限环
invariant set,quadratic system in plane,limit cycle
