In this work, we are going to obtain approximate solutions for Lie ́nard equations using He's variational iteration method. This method proves to be very promising for obtaining approximate solutions for this kind of equations. We also demonstrate the superiority of variational iteration method over the decomposition method for this type of equations providing numerical comparisons.

In this paper, we consider variational iteration method (VIM) to obtain exact solution to the Fisher’s equation. The variational iteration method is based on Lagrange multipliers for identification of optimal value of parameters in a functional. Using this method, it is possible to find the exact solution or an approximate solution of the problem.