Qualitative Analysis of Van der Pol Type Equation with Periodic Forcing Term

In this paper we analyze the qualitative behaviour of the equationε+q(X) +εX=bp(t),where e is a small parameter.We divide the interval of parameter b into four sets of subintervals,A,B,C and D.For bA,B or D,we discuss the different structures of the attractors of the equationand their stabilities.When chaotic phenomena appear,we also estimate the entropy.For bC,theset of bifurcation intervals,we analyze the bifurcating type and get a series of consequences from theresults of Newhouse and Palis.