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Homework Help: Matrix Multiplication

  1. Jan 24, 2009 #1
    Where A = a 2*2 matrix, is the following true:

    (A^n)(A^m) = (A^m)(A^n)

    Thanks in advance
     
  2. jcsd
  3. Jan 24, 2009 #2

    Dick

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    Take a guess. Tell us why it might be true.
     
  4. Jan 24, 2009 #3
    Well I think it would be true, however I know that matrix multiplication is non-commutative so I wasnt sure.

    Thanks
     
  5. Jan 24, 2009 #4

    Dick

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    Matrix multiplication isn't commutative in general. But this is special. It IS associative. Both sides of that equation have n+m A's. They are just grouped differently.
     
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