The document discusses two methods for evaluating integrals: integration by substitution and integration by parts. Integration by substitution involves setting up an integral in a way that allows substituting a new variable u for an expression involving x, making the integral easier to evaluate. Integration by parts is a method for evaluating integrals of products of functions by breaking it into multiple integrals using the formula ∫u v dx = u∫v dx −∫u' (∫v dx) dx. The document provides examples of applying both methods to evaluate integrals of trigonometric, logarithmic, and exponential functions. It also briefly mentions partial fractions as a method to decompose rational functions into simpler fractions.