【摘要】 本文讨论一类平面三次系统存在周期解的充分条件,分别对自治和非自治系统给出了两个定理。更多还原

【Abstract】 This paper deals with the existence of periodic solutions in a class of planar cubic systems, both autonomous and nonautonomous. As a result, two theorems are given to ensure the existence of periodic solutions of autonomous and nonautonomous systoms respectively.更多还原