Abstract
In this research, we consider a quasiperiodic system of nonlinear differential difference equations. We prove a new theorem to solve these equations. It says that one can always assure the existence of quasiperiodic solution by checking several conditions on an obtained approximate solution and further give a method to obtain an error bound of the approximate solution. The approximate solutions are constructed by the method of Galerkin's procedure based on trigonometric polynomials. We carry out some numerical experiments using the method of Galerkin's procedure.
