The convergence of operational Tau method for solving a class of nonlinear Fredholm fractional integro-differential equations on Legendre basis

In this paper, we investigate approximate solutions for nonlinear Fredholm integro-differential equations of fractional order. We present an operational Tau method by obtaining the Tau matrix representation. We solve a special class of nonlinear Fredholm integro-differential equations based on Legendre-Tau method. By using the Sobolev inequality and some of Banach algebra properties, we prove that our proposed method converges to the exact solution in L^2-norm.