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Question
Compute the indicated product.
`[(2,1),(3,2),(-1,1)][(1,0,1),(-1,2,1)]`
Solution
`[(2,1),(3,2),(-1,1)][(1,0,1),(-1,2,1)]`
`= [(2(1)+1(-1), 2(0)+1(2), 2(1)+1(1)), (3(1)+2(-1), 3(0)+2(2), 3(1)+2(1)), (-1(1)+1(-1), -1(0)+1(2), -1(1)+1(1))]`
`= [(2-1,0+2, 2+1), (3-2,0+4, 3+2),(-1-1, 0+2,-1+1)]`
`= [(1,2,3),(1,4,5),(-2,2,0)]`
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