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Homework Help: Simple cross product question. Please help

  1. May 13, 2009 #1
    simple cross product question. Please help!!!

    1. The problem statement, all variables and given/known data

    Hey guys, I know how cross product works,

    i-->j-->k : positive numbers
    i<--j<--k : negative number

    2. Relevant equations

    The question that I have is, say I have -k x -i, I am supposed to get a positive j since the two negatives cancel out, is that correct? I would really appreciate any help, I have a final in less than 10 hours and would love a quick response! :)
  2. jcsd
  3. May 13, 2009 #2


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    Science Advisor
    Homework Helper

    Re: simple cross product question. Please help!!!

    (-k)x(-i) is +j. Yes, it's the same as (k)x(i).
  4. May 13, 2009 #3
    Re: simple cross product question. Please help!!!

    excellent! thanks for your quick response. Now, to continue studying for this nasty final! :)
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