${\displaystyle \underset{\phantom{}}{\overset{\phantom{}}{}}}(x^2+x)cos(x)dx={\displaystyle \underset{\phantom{}}{\overset{\phantom{}}{}}}v{u}^{\text{'}}dx=\left[\begin{array}{cc}{u}^{\text{'}}& v\\ u& v^{\text{'}}=\end{array}\right]=====x^2+x===x^2+x=cos(x)=$dots

Find u and$/$or$,v^{\text{'}}$

$v^{\text{'}}=2x+1$

$u=-sin(x)$

$v^{\text{'}}=\frac{x^3}{3}+\frac{x^2}{2}$