Description: Analysis of boundary and initial value problems. Dirichlet problem for Laplace's equation, variational formulation, Rayleigh-Ritz principle, Sobolev spaces, weak solutions, convergence of the finite element method, interior and boundary regularity, heat equation and the Gaussian kernel, energy estimates, maximum principle, stability, consistency, and convergence of numerical methods, the Fourier transform, Fourier synthesis of Green's functions for the wave equation, von Neumann analysis of finite difference methods for waves.