/ _____\ atan\\/ 4*x /
d / / _____\\ --\atan\\/ 4*x // dx
1 --------------- ___ \/ x *(1 + 4*x)
/ 1 4 \ -|--- + -------| \2*x 1 + 4*x/ ----------------- ___ \/ x *(1 + 4*x)
32 3 4 ---------- + ---- + ----------- 2 2 x*(1 + 4*x) (1 + 4*x) 4*x ------------------------------- ___ \/ x *(1 + 4*x)