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Homework Help: Decoding encryption with matrices

  1. Dec 8, 2004 #1
  2. jcsd
  3. Dec 8, 2004 #2


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    Find the inverse of A and left-multiply it by the coded matrix. Call B the message matrix, and B' the coded matrix. You get the coded matrix by finding

    AB = B'

    Get the uncoded matrix by taking

    A^(-1)B' = A^(-1)AB = IB = B
  4. Dec 8, 2004 #3


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    They give the inverse matrix of A just above the sentence "I LOVE MONICA". It appears to be off though, and is actually the negative of the inverse.
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