atan(x) ------- 3 x
1 3*atan(x) ----------- - --------- 3 / 2\ 4 x *\1 + x / x
/ 1 3 6*atan(x)\ 2*|- --------- - ----------- + ---------| | 2 2 / 2\ 3 | | / 2\ x *\1 + x / x | \ \1 + x / / ----------------------------------------- 2 x
/ 2 15*atan(x) 4 9 \ 4*|--------- - ---------- + ------------ + -----------| | 3 5 2 4 / 2\| |/ 2\ x 2 / 2\ x *\1 + x /| \\1 + x / x *\1 + x / / ------------------------------------------------------- x