| This work is about the existence of the limit cycle of equation ｘ＋ｆ（ｘ）＋ｇ（ｘ）＝０, where g(x) has two discontinuous points and does not satisfy g(x)·x>0,x≠0 . We use the concept of Fillipov solution defined in 4,5 and get several theorems of existence of limit cycle. |
