(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Is the line through (4,1,-1) and (2,5,3) parallel to the line through (-3,2,0) and (5,1,4)?

2. Relevant equations

3. The attempt at a solution

Line one 'direction' = (-2,4,4) = A

Line two 'direction' = (8,-1,4) = B

I remember that the cross product of two vectors is zero if they are parallel, but AxB is not the zero vector; the answer in the book says theyare indeedparallel...

Is this not the right method?

Cheers,

Adrian ^^

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# Homework Help: Cross product for parallel vectors

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