(New page: ==Info from question== <math>\left[ \begin{array}{ccc} 1 & 0 & 4 \\ 0 & 1 & 0 \\ 1 & 0 & 1 \end{array} \right] \times \left[ \begin{array}{ccc} X \end{array} \right] = \left[ \begin{arr...) |
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==1. How can Bob decrypt the message?== | ==1. How can Bob decrypt the message?== | ||
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| + | Since Bob already knows the matrix [X] and the encrypted matrix, all he has to do to find the original matrix is to invert [X] and multiply with the encrypted matrix. | ||
Revision as of 09:32, 18 September 2008
Info from question
$ \left[ \begin{array}{ccc} 1 & 0 & 4 \\ 0 & 1 & 0 \\ 1 & 0 & 1 \end{array} \right] \times \left[ \begin{array}{ccc} X \end{array} \right] = \left[ \begin{array}{ccc} 2 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 3 \end{array} \right] $
1. How can Bob decrypt the message?
Since Bob already knows the matrix [X] and the encrypted matrix, all he has to do to find the original matrix is to invert [X] and multiply with the encrypted matrix.
