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Question
Compute the indicated products:
`[[1 -2],[2 3]][[1 2 3],[-3 2 -1]]`
Solution
`[[1 - 2],[2 3]][[1 2 3],[-3 2 -1]]`
`⇒[[1xx1+(-2xx(-3) 1xx2+(-2)xx2 1xx3+(-2)xx(-1)]],[2xx1+3xx(-3) 2xx2+3xx2 2xx3+3xx(-1)]]`
`⇒ [[1+6 2-4 3+2],[2-9 4+6 6-3]]`
`⇒[[7 -2 5],[-7 10 3]]`
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