Consider the indefinite integral 01x2(x33)3 dx\displaystyle {\int_{{0}}^{{1}}}\frac{{x}^{{2}}}{{\left({x}^{{3}}-{3}\right)}^{{3}}}\ {\left.{d}{x}\right.}:

This can be transformed into a basic integral by letting

u=\displaystyle {u}=   and

du=\displaystyle {d}{u}=dx\displaystyle {\left.{d}{x}\right.}  

Performing the substitution yields the integral

ab\displaystyle {\int_{{a}}^{{b}}}du\displaystyle {d}{u}  
where a = and b =