On the Existence of Periodic Solutions for n-Dimensional Li nard Equations with Delay

The present article considers the existence of T-periodic solutions for the following Lienard equation with delay.where h≥0 is a constant, (Rn, R), (Rn, R), (R, Rn), p(t+T)=p(t) for a constant T>0 and . By use of V-function and coincidence degree. The result proposed by Ge Weigao is extended to the case of delay-differential system in the papee. One feature of our result is that the delay has a notable impact on the existence of periodic soultion.