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After that, he needs to calculate C*B`. By finding its corresponding order in the alphabet, He can figure our what she wants to say. | After that, he needs to calculate C*B`. By finding its corresponding order in the alphabet, He can figure our what she wants to say. | ||
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Revision as of 07:03, 19 September 2008
Application of linearity
How can Bob decrypt the message?
Assuming that Matrix A is what Alice wants to say, and matix B is a 3-by-3 matrix to encrypt Alice's message, and matrix C is the encoded messange.
It can be expressed A*B=C.
In order to find A, Bob needs to find the inverse matrix of B.
A*B*B`= C*B`, A*I=C*B'
After that, he needs to calculate C*B`. By finding its corresponding order in the alphabet, He can figure our what she wants to say.
