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Veryfying a simple formule.

  1. Oct 4, 2009 #1
    1. The problem statement, all variables and given/known data
    Hi all my new friends..
    A and B are vectors, A.B = B.A

    2. Relevant equations

    3. The attempt at a solution

    How we can veryfy that this formula is correct?
  2. jcsd
  3. Oct 4, 2009 #2
    I'm assuming you mean a scalar product.

    A.B = ABcos(x)
    B.A = BAcos(x)

    AB = BA since arithmetic multiplication is commutative.
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