If A2,3,−1, B5,6,3, C2,−3,1 are the vertices of triangle ABC, the length of the median AD is
362
36
552
332
The midpoint of the side BC is D=72,32,2
The length of the median ADis
AD=72−22+32−32+−1−22 =94+94+9 =332
Therefore, the length of the median AD is 332