2 x *atan(x)
2 x ------ + 2*x*atan(x) 2 1 + x
/ 3 \ | x 2*x | 2*|- --------- + ------ + atan(x)| | 2 2 | | / 2\ 1 + x | \ \1 + x / /
/ 2 4 \ | 7*x 4*x | 2*|3 - ------ + ---------| | 2 2| | 1 + x / 2\ | \ \1 + x / / -------------------------- 2 1 + x