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Math Help - odd verctor problem

  1. #1
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    odd verctor problem

    a,b,c,d,e and f are all verctors
    proof: (ab,cd,ef)=(a,b,d)(c,e,f)-(a,b,c)(d,e,f)
    ps:It rather confuses me that the verctors are restricted in parentheses oderly.I will appreciate it if you show the meaning of this.
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  2. #2
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    Re: odd verctor problem

    Hey CosmoBlazer.

    I agree that the notation is confusing. Can you possibly show us where you got the definition from? Also you might want to check if its a scalar triple product:

    Triple product - Wikipedia, the free encyclopedia
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  3. #3
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    Re: odd verctor problem

    What does "(ab,cd,ef)" mean? axb etc are vectors. What does a triple of vectors mean? What does "(a,b,d)(c,e,f)-(a,b,c)(d,e,f)" mean? If "(a, b, c)" is the triple product of vectors as chiro suggests is the " \cdot" just multiplication of numbers?
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  4. #4
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    Re: odd verctor problem

    I believe (a,b,c) is a.bxc, a scalar. Then try to prove eq in post 1. If you can, it is.
    Last edited by Hartlw; August 23rd 2013 at 06:11 AM. Reason: added "a scalar"
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  5. #5
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    Re: odd verctor problem

    To start off the proof, note:
    (a,b,c)=a.bxc
    ax(bxc)=(a.c)b-(a.b)c
    (axb).(cxd)=(b.d)(a.c)-(b.c)(a.d)
    which come from vector algebra texts.

    Then apply to post 1
    (axb,cxd,exf) = axb.(cxdxexf)
    cxdxe=(c.e)d-(c.d)e
    cxdxexf=(c.e)dxf-(c.d)exf
    (..)=(c.e)axb.dxf-(c.d)axb.exf

    and continue on as a good excersize. let us know how you make out.
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