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 our resuls do not require that the damping must be positire.
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 our resuls do not require that the damping must be positire.
