U-substitution is a technique used to simplify integrals by substituting a new variable for part of the original expression.
The chain rule is used in differentiation to find derivatives when there are nested functions.
Integration by parts is another integration technique that involves breaking down an integral into two parts and applying specific rules.
Trigonometric substitutions are special cases of u-substitution where trigonometric identities are used to simplify integrals involving trigonometric functions.