Distributions: Test Functions and Distributions on iir; Derivatives of Distributions, Convolutions, Tempered Distributions; Sobolev Spaces: Domains in iir, Extension Operators, Inclusion Theorems, Compactness Theorems, Trace Theory; Weak Solutions of Elliptic Problems: The Lax- Milgram Lemma and Variations; Examples of Elliptic Problems, Regularity of Weak Solutions, Elementary Theory of the Finite Element Method; Semi-Groups and Applications: Unbounded Operators on a Banach Space, Co-Semigroups, Applications to the Wave Equation, The Inhomogeneous Equation; Appendix 1: The Topology on D; Appendix 2: Vector-Valued Integration.