________
/ 2
asin(x) x*\/ 1 - x
------- - -------------
2 2 0.5*asin(x) - 0.5*x*(1.0 - x^2)^0.5
________
/ 2
- x*\/ 1 - x + asin(x)
-------------------------
2 / ________\
| / 2 |
-\-asin(x) + x*\/ 1 - x /
----------------------------
2