Matrix

greg1313

Forum Staff
Oct 2008
8,008
1,174
London, Ontario, Canada - The Forest City
Actually, I moved the post here - but $\LaTeX$ is probably a good place to start. :eek:
 
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greg1313

Forum Staff
Oct 2008
8,008
1,174
London, Ontario, Canada - The Forest City
$$\begin{bmatrix}
x_{11}&x_{12}&x_{13} \\
&. \\
&. \\
&. \\
x_{n-2}&x_{n-1}&x_n
\end{bmatrix}$$
 
Sep 2018
3
0
USA
Hello, there was a matrix problem I was unable to work out completely:

'Your task is to crack the following code and find the encrypted word.

To make your task easier, the following information about the encoding matrix is given:

Position 1,1 in the encoding matrix is an even number
The decoding matrix only contains integers
Position 1,1 in the encoding matrix is the negative of the number in position 1,1 in the decoding matrix
Modulo arithmetic hasn't been used
My coded message is:

91, -38, 137, -59, 145, -59

How would I go about solving it; I know that E^-1 x EA will decipher the message. But would I place it in a 2x2 or a 3x3 matrix? How would I work out the encoding matrix? Thank you in advance!