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