x*acos(3*x)
3*x - ------------- + acos(3*x) __________ / 2 \/ 1 - 9*x
/ 2 \ | 9*x | -3*|2 + --------| | 2| \ 1 - 9*x / ----------------- __________ / 2 \/ 1 - 9*x
/ 2 \ | 27*x | -27*x*|4 + --------| | 2| \ 1 - 9*x / -------------------- 3/2 / 2\ \1 - 9*x /