Complex Tanh-Function Expansion Method and Exact Solutions to Two Systems of Nonlinear Wave Equations

The complex tanh-function expansion method was presented recently, and it can be applied to derive exact solutions to the Schrödinger-type nonlinear evolution equations directly without transformation. In this paper, the complex tanh-function expansion method is applied to derive the exact solutions to the general coupled nonlinear evolution equations. Zakharov system and a long-short-wave interaction system are considered as examples, and the new applications of the complex tanh-function expansion method are shown.