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Homework Help: Need help with combination of dot product and cross product question

  1. Nov 1, 2009 #1
    1. The problem statement, all variables and given/known data

    Let [tex]\vec{A}[/tex], [tex]\vec{B}[/tex], and [tex]\vec{C}[/tex] be three vectors which are all not in the same plane. Show that [tex]\vec{A}{\cdot}(\vec{B}{\times}\vec{C})=\vec{B}{\cdot}(\vec{C}{\times}\vec{A})=\vec{C}{\cdot}(\vec{A}{\times}\vec{B})[/tex]

    2. Relevant equations

    Don't know :(

    3. The attempt at a solution

    Well I looked up some algebraic properties of dot products and cross products, but nothing that relates the two. I tried working it out, but it's getting extremely messy.
  2. jcsd
  3. Nov 1, 2009 #2


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  4. Nov 1, 2009 #3
    thank you, but that link is really complicated and i dont understand it.

    as for brute force, that would be so long and tedious, and the probability of making a minor error which results in an incorrect answer is so high

    is there any easier way to do it?


    nevermind, I got it, brute force worked, thanks
    Last edited: Nov 1, 2009
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