“…The simplicity in building the wavelet bases from any function which use only two operations translation and dilation [3], this can be easily seen in Haar wavelet.The simple form of the mother function in Haar wavelet as we see below makes the processes of dilation and translation an easy work and the introduced wavelet family is orthogonal not only linearly independent. Although, the wavelet function appeared in 1910, their use in the solution of differential equations does not appear until recently [4][5][6], last twenty years.In 2017 Kaoud and El Dewaik, [7] have used Haar wavelet technique to solve Poisson's equation on a unit square domain with collocation points j/16 , j = 1, 3, . .…”