In this paper, we propose and analyze a spectral Chebyshev-Legendre
approximation for fractional order integro-differential equations of Fredholm
type. The fractional derivative is described in the Caputo sense. Our proposed
method is illustrated by considering some examples whose exact solutions are
available. We prove that the error of the approximate solution decay
exponentially in L^2-norm.Comment: 20 pages, 5 figures, 1 tabl