Tau spectral methods and Adomian’s decomposition can be fruitfully combined to quickly approximate the analytical solution of any time-dependent partial differential equation with boundary conditions defined on the four sides of a rectangle. In this work, combinations of Legendre polynomials have been used to generate orthogonal two-dimensional polynomials on a rectangular domain. The time evol...

Common practice is to recommend evaluation of polynomials by Horner’s rule. Here’s an example where it is fast but doesn’t work nearly as accurately as another fairly easy method. Can a method for Legendre polynomials be both fast and accurate? 1 1 Legendre Polynomials A substantial literature has grown up around the uses for orthonormal polynomials. Here we look at the example of Legendre poly...