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Homework Help: Cross Product

  1. Oct 9, 2005 #1
    I have two vectors A = 2x + 3y - 4z and B = -6x - 4y + z. The problem asks me to find the component of A X B along the direction of C = x - y + z. So I did put A and B into a matrix, but I didn't get the correct answer, which is -14.4. What am I doing wrong?
     
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  3. Oct 9, 2005 #2

    mezarashi

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    First, find the vector D = A X B.
    Then find the unit vector in the C direction.
    Finally dot D with the unit vector of C.
     
  4. Oct 9, 2005 #3
    I got -15 instead of -14.4 (the answer from the back of the book). I am not sure why it's a little off.
     
  5. Oct 9, 2005 #4

    mezarashi

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    I can only suggest an algebriac mistake.
     
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