Question 755834: a cube measures 1 by 1 by 1. A lline is drawn from one vertex to the digagonally opposite vertex through the centre of the cube this is called thhe body diagonal of the cube. determine the angles between the body diagonals on the cube one goes from point (1,0,0) to (1,1,1) and the other goes from (1,1,0) to (0,0,1)
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! a cube measures 1 by 1 by 1. A lline is drawn from one vertex to the digagonally opposite vertex through the centre of the cube this is called thhe body diagonal of the cube. determine the angles between the body diagonals on the cube one goes from point (1,0,0) to (1,1,1) and the other goes from (1,1,0) to (0,0,1)
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Those 2 lines don't intersect, maybe there's a typo.
Label the points.
A(1,0,0) to B(1,1,1) and the other goes from C(1,1,0) to D(0,0,1)
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If you translate them to pass thru the Origin (or use 2 vectors thru the Origin, parallel to AB and CD, same thing), you can find the angle between them.
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AB --> (0,1,1) = vector u
CD --> (-1,-1,1) = vector v
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A•B = 0 - 1 + 1 = 0
cos = 0
--> angle = 90 degs
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