### Integration by Substitution

Integration by Substitution This method is also called the u-substitution or the reverse of chain rule of derivation. The chain rule except being useful in derivation is also in integration: If we have two functions $ displaystyle f(x)$ and $ displaystyle g(x)$ then the derivative of their composite function is:$ displaystyle (fcirc g{)}'(x)={f}'(g(x)){g}'(x)$. How it helps on integration […]