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Homework Help: Volume of a parallelepiped

  1. Sep 29, 2012 #1
    1. The problem statement, all variables and given/known data

    Find the volume of the parallelepiped with adjacent edged PQ, PR, and PS.
    P (-2,1,0)
    Q (2,3,2)
    R (1,4,-1)
    S (3,6,1)

    2. Relevant equations

    Volume = PQ . (PR x PS)

    3. The attempt at a solution

    I first found the vectors PQ, PR and PS. Then I did the cross product of PR x PS and then did the dot product of PQ (dot) PR x PS. I got an answer of 6, but the answers in the back of the book says 16. Did I do it wrong? or is the book wrong?
  2. jcsd
  3. Sep 29, 2012 #2
    Nevermind, I found out what I did wrong. I calculated on of the vectors wrong.
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