asin(7*x)
d --(asin(7*x)) dx
7 -------------- ___________ / 2 \/ 1 - 49*x
343*x -------------- 3/2 / 2\ \1 - 49*x /
/ 2 \ | 147*x | 343*|1 + ---------| | 2| \ 1 - 49*x / ------------------- 3/2 / 2\ \1 - 49*x /