(701, #55) Find the angle between a diagonal of a cube and one of its

(701, #55) Find the angle between a diagonal of a cube and one of its edges.

Solution: The vector < 1, 1, 1 > is the diagonal. The vector < 0,0,1 > is an edge. We compute the angle between them and find that is 54.7:

By symmetry the angle between the diagonal and the other edges is the same.
Ans:

by: gm