put x=t2, then integral reduces to...
2∫t.tan-1(1+t)dt
now use integration by parts... considering 'tan-1(1+t)' as first function and 't' as second function...
put x=t2, then integral reduces to...
2∫t.tan-1(1+t)dt
now use integration by parts... considering 'tan-1(1+t)' as first function and 't' as second function...