Numerical Solution of Klein-Gordon Equation by Using the Adomian's Decomposition and Variational Iterative Methods

In this paper , a klein-gordon equation is solved by using the adomian 's decomposition method, var iational iteration method and modified form of these methods. t he approximate solution of this equation is calculated in the form of series in which its components ar ecomputed by applying a recurs ive relation. the existence and uniqueness of the solution and the convergence of the proposed met hods are proved. a numerical example is studied to demonstrate the accuracy of the presented methods.