/ ________\
| / 2 |
atan\\/ x - 1 /
atan(sqrt(x^2 - 1))
/1 1 \
-|-- + -------|
| 2 2|
\x -1 + x /
----------------
_________
/ 2
\/ -1 + x
2 1 3*x
-- + ----------- + ----------
3 / 2\ 2
x x*\-1 + x / / 2\
\-1 + x /
-----------------------------
_________
/ 2
\/ -1 + x