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Math Help - Prove this cross product and dot product = a scalar of itself

  1. #1
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    Prove this cross product and dot product = a scalar of itself


    If i simply right this all down with a1b1c1 etc, will this be a valid proof? Or is there some quick way to prove it I am not seeing.

    edit : I have proved it by writing it out the long way, but is there a quicker method?
    Last edited by lukasaurus; April 11th 2013 at 11:52 AM.
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    Re: Prove this cross product and dot product = a scalar of itself

    Quote Originally Posted by lukasaurus View Post

    If i simply right this all down with a1b1c1 etc, will this be a valid proof? Or is there some quick way to prove it I am not seeing.

    edit : I have proved it by writing it out the long way, but is there a quicker method?
    a \cdot (b \times (mb + c)) = a \cdot (b \times (mb) + b \times c )

    = a \cdot (m b \times b + b \times c)

    Can you finish?

    -Dan
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