Problem $1)$ Evaluate using integration by parts. $[5$ points.$]$

${\displaystyle \underset{\phantom{}}{\overset{\phantom{}}{}}}(x-1)(sin(x))dx$

Problem $2)$ Evaluate using trigonometric substitution.$[5$ points.$]$

${\displaystyle \underset{0}{\overset{\frac{}{2}}{}}}si{n}^{2}x*co{s}^{2}xdx$