Periodic Perturbations of Non-Conservative Second Order Differential Equations

Abstract

Consider the Lienard system $u^{\prime \prime }+f(u)u^{\prime }+g(u)=0$ with a center at the origin 0. In the case where the period function $T$ is monotonic, we examine periodic solutions of the perturbed equation $u^{\prime \prime }+a(u)u^{\prime }+f(u)=\epsilon h(t)$. {\it Key Words:} perturbed systems, Lienard equation, polynomial systems.

7 pages