Hellp

for a task about the launch of a rocket we had to make a matrix OPL3 with in the first column the time T and in the second column the height of the rocket at that time.

I must Maple find the time where the rocket is at his highest point.

I can find how high the highest point is, but didn't succeed to find the corresponding time.
Can Maple tell me at wich time (= row # o/t matrix OPL3) the rocket is at his highest point.

I used the following to find the highest point.

ymin:=min(seq(abs(OPL3(i,2)),i=64..830));

Note: the diff equitation is numerically solved, so I can't use solve(....=0) (am I right here?)

Thanks!