(G′/G)-Expansion Method Equivalent to Extended Tanh Function Method

Abstract

In a recent article [Physics Letters A 372 (2008) 417], Wang et al. proposed a method, which is called the (G′/G)-expansion method, to look for travelling wave solutions of nonlinear evolution equations. The travelling wave solutions involving parameters of the KdV equation, the mKdV equation, the variant Boussinesq equations, and the Hirota–Satsuma equations are obtained by using this method. They think the (G′/G)-expansion method is a new method and more travelling wave solutions of many nonlinear evolution equations can be obtained. In this paper, we will show that the (G′/G)-expansion method is equivalent to the extended tanh function method.