x*acos(2*x)
d --(x*acos(2*x)) dx
2*x - ------------- + acos(2*x) __________ / 2 \/ 1 - 4*x
/ 2 \ | 2*x | -4*|1 + --------| | 2| \ 1 - 4*x / ----------------- __________ / 2 \/ 1 - 4*x
/ 2 \ | 12*x | 8*x*|-4 + ---------| | 2| \ -1 + 4*x / -------------------- 3/2 / 2\ \1 - 4*x /