Respostas

2014-08-21T16:10:29-03:00
Olá! 

At =   \left[\begin{array}{ccc}a11&a12\\a21&a22\\a31&a32\end{array}\right] \\\\
At =   \left[\begin{array}{ccc}2*1 + 3*1&2*1+3*2\\2*2+3*1&2*2+3*2\\2*3+3*1&2*3+3*2\end{array}\right] \\\\
At =   \left[\begin{array}{ccc}5&8\\7&10\\9&12\end{array}\right]

Espero que tenha ajudado!
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