atan(2*x) 2*5 *log(5) ------------------- 2 1 + 4*x
atan(2*x) 4*5 *(-4*x + log(5))*log(5) ----------------------------------- 2 / 2\ \1 + 4*x /
/ 2 2 \ atan(2*x) | log (5) 32*x 12*x*log(5)| 8*5 *|-2 + -------- + -------- - -----------|*log(5) | 2 2 2 | \ 1 + 4*x 1 + 4*x 1 + 4*x / ------------------------------------------------------------ 2 / 2\ \1 + 4*x /