Applications of extended tanh method to ‘special’ types of nonlinear equations

摘要

In this paper, we explore more applications of extended tanh method to some special nonlinear equations. Such equations are not of differential polynomial form so that cannot be directly dealt with by tanh method or extended tanh method. As examples, we apply a recently proposed extended tanh method to build some new explicit solutions for (2+1)-dimensional sine-Gordon equation, Dodd–Bullough–Mikhailov equation and coupled Schrödinger-KdV equation.