atan(4*x) 4*2 *log(2) ------------------- 2 1 + 16*x
atan(4*x) 16*2 *(-8*x + log(2))*log(2) ------------------------------------ 2 / 2\ \1 + 16*x /
/ 2 2 \ atan(4*x) | log (2) 128*x 24*x*log(2)| 64*2 *|-2 + --------- + --------- - -----------|*log(2) | 2 2 2 | \ 1 + 16*x 1 + 16*x 1 + 16*x / --------------------------------------------------------------- 2 / 2\ \1 + 16*x /