8 6 x x -- - -- + acos(x) 8 6
x^8/8 - x^6/6 + acos(x)
7 5 1 x - x - ----------- ________ / 2 \/ 1 - x
/ 1 3 5\ x*|- ----------- - 5*x + 7*x | | 3/2 | | / 2\ | \ \1 - x / /
2 1 3 5 3*x - ----------- - 20*x + 42*x - ----------- 3/2 5/2 / 2\ / 2\ \1 - x / \1 - x /