Evaluate: `intxtan^2x\ dx`

Explanation

`int x tan^2x dx`

`=intx(sec^2x-1)dx`

`=intx sec^2 x dx - int x dx`

`=(x(tanx) - int tanx dx ) - (x^2)/2+c`
`
=x tanx - ln|secx|-(x^2)/2+c`
`
int x tan^2 x dx = xtanx- ln |secx| - (x^2)/2+c`