411 REFERENCE · Wikibooks
A-level Mathematics/MEI/C3/Integration
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Integration
Integration by Substitution
Integration by Parts
Integration by parts is used when you have two functions multiplied together, such as ln x and a simple polynomial, where 1 function is not the derivative of the other. As an example:
In this expression use the substitutions: and . In almost all other expressions, the polynomial is taken as u. After substituting, the expression in the example becomes:
After integrating and differentiating the respective parts of the expression, this becomes: