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Question
Compute the indicated product.
`[(1, -2),(2,3)][(1,2,3),(2,3,1)]`
Solution
`[(1, -2),(2,3)][(1,2,3),(2,3,1)]`
`=[(1xx1+(-2)xx2, 1xx2(-2)xx3, 1xx3(-2)xx1), (2xx1+3xx2, 2xx2+3xx3, 2xx3+3xx1)]`
`= [(1-4, 2-6, 3-2),(2+6, 4+9, 6+3)]`
`= [(-3, -4, 1),(8 ,13,9)]`
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