Applied Mathematics and Mechanics (English Edition) ›› 1995, Vol. 16 ›› Issue (12): 1171-1174.
董勤喜1, 黄先开2
Dong Qinxi1, Huang Xiankai2
摘要: In this paper, by using of the theory of coincidence degree,we obtain the new conditions which guarantee the existence of harmonic solutions for Lienard Systems x=d/dt grad F(x)+grad G(x)=p(t) our resuls do not require that the damping must be positive.