The paper includes four parts. In the first part, the latest progresses and some important results about the bifurcation theory of planar dynamical systems are stated ;In the second part, by using the Tkachev method which concerned with the proof of the stability of a multiple limit cycle, the exact computation formula of h3(T) for the multiple limit cycle bifurcation for a given system is given; In the third part , proof of the convergence of h3(T) as Tâ†'∞ is shown; At the last part , a computation formula for higher separatrix values(k > 3) is conjectured. |