“…In the open literature, there are many analytical methods for fractional differential equations, for example, the exp-function method [31], the direct algebraic method [32,33], the variational approach [34][35][36], Fourier spectral method [37] and the reproducing kernel method [38], and the frequency analysis method [39], this paper shows the VIM is as effective as the homotopy perturbation method for fractional calculus. The examples show the solution process is simple, and the results are of high accuracy.…”