x*atan(3*x)
3*x -------- + atan(3*x) 2 1 + 9*x
/ 2 \ | 9*x | 6*|1 - --------| | 2| \ 1 + 9*x / ---------------- 2 1 + 9*x
/ 2 \ | 9*x | 216*x*|-1 + --------| | 2| \ 1 + 9*x / --------------------- 2 / 2\ \1 + 9*x /