Trigonometric methods as special case of exp function method

In this paper, the Exp function method is compared with tanh and tanh-coth methods, to solve partial differential equations. It has been shown that the second and third methods are special cases of the first method. To illustrate and clarify the idea, exact solutions of the modified equal width wave equation are obtained by Exp function method and the results have been compared with those of tanh and tanh-coth methods.