This paper reveals the seeming ambiguity problem of the method of multiple scales in solving the third or higher order approximate solutions of nonlinear systems through an example of the famous van der Pol equation. By comparing the results obtained by the method of multiple scales with that of the KBM method, the paper indicates a proper way about how to apply the method of multiple scales to solving the third or higher order approximate solutions of nonlinear systems.
王怀磊,胡海岩.关于多尺度法的一个注记[J].动力学与控制学报,2004,2(3):10~13; Wang Huailei, Hu Haiyan. A note on the method of multiple scales[J]. Journal of Dynamics and Control,2004,2(3):10-13.