/ 1 \ -2*|------- + 3*x| \atan(x) / ---------------------- 2 / 2\ 2/3 9*\1 + x / *atan (x)
/ 2 \ | 5 36*x 18*x | 2*|-9 + ----------------- + ------ + ----------------| | / 2\ 2 2 / 2\ | \ \1 + x /*atan (x) 1 + x \1 + x /*atan(x)/ ------------------------------------------------------ 2 / 2\ 2/3 27*\1 + x / *atan (x)