1 / | | atan(a*x) dx | / 0
1 / 0 for a = 0 / | | | / 2\ | atan(a*x) dx = < log\1 + a / | |- ----------- + atan(a) otherwise / | 2*a 0 \
// 0 for a = 0\
|| |
/ || / 2 2\ |
| || log\1 + a *x / |
| atan(a*x) dx = C + |<- -------------- + a*x*atan(a*x) |
| || 2 |
/ ||-------------------------------- otherwise|
|| a |
\\ /