Rational solutions of integrable equations via nonlinear superposition formulae

In this paper, a method is developed to obtain rational solutions of integrable equations which include KdV, Boussinesq, KP, Ito, (1 + 1)-dimensional CDGKS, Ramani and (2 + 1)-dimensional CDGKS equations. The key step that we use to find rational solutions of these equations is the use of nonlinear superposition formulae. Ail these rational solutions obtained for each equation are connected by a Backlund transformation, which enables us to find other new solutions through the nonlinear superposition of rational solutions and other known solutions.