/ 2\ acos\x /
acos(x^2)
-2*x ----------- ________ / 4 \/ 1 - x
/ 4 \ | 2*x | -2*|1 + ------| | 4| \ 1 - x / --------------- ________ / 4 \/ 1 - x
/ 4 \ 3 | 6*x | -4*x *|5 + ------| | 4| \ 1 - x / ------------------ 3/2 / 4\ \1 - x /