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Minihoudini
Oct17-11, 02:38 PM
The question is:
let V1=(2,2,0), V2=(-1,2,1), V3-(1,1,4). There three vectors determine a parallelepiped. P draw it.
(a) (this is the one that is giving me trouble) Determine the length of its main diagonal. (from origin to opposite vertex).

I can't seem to figure out what it means from the origin to the opposite vertex. I've drawn the graph and originally I thought I would have to take the determine of two vectors then find the length of it. I'm just pretty lost here. Once I get this part and I know what its asking of me I can get the other problems easily.

mathman
Oct17-11, 03:32 PM
The origin is (0,0,0). The opposite vertex is the point at the end of the vector V1+V2+v3 (with one end at the origin), that is (2,5,5).

I assume you know how to get this length.

Minihoudini
Oct18-11, 12:46 PM
thanks, that helped a lot