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Math Help - proove involving dot product and zero vector

  1. #1
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    proove involving dot product and zero vector

    Show that if \vec u \cdot \vec v = \vec 0 for all vectors \vec v then \vec u=\vec 0
    I know that 0 divided by v is 0, but how do I right that in terms of linear algebra?

    It makes sense because any number multiplied with 0 will be 0, then it's just a sum of 0s, but I don't know how to give a formal proof
    Last edited by superdude; February 9th 2010 at 08:50 PM. Reason: fixed question
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  2. #2
    MHF Contributor Bruno J.'s Avatar
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    There is no statement. Your sentence makes as much sense as "If I take the bus."

    Moreover, whatever you meant to say, you cannot divide by \vec v, it's a vector.
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  3. #3
    MHF Contributor Bruno J.'s Avatar
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    Hint : consider \vec u \cdot \vec u.
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