Question 352572
[A]={{{(matrix(3,3,3,6,-1,3,-3,5,9,9,-2))}}}
[x]={{{(matrix(3,1,x,y,z))}}}
[b]={{{(matrix(3,1,7,-12,12))}}}
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[A][x]=[b]
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[x]=[A]inv[b]
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det([A])={{{135}}}
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[A]inv={{{(1/135)*(matrix(3,3,-39,3,27,51,3,-18,54,27,-27))}}}
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[x]={{{(matrix(3,1,1/9,7/9,-2))}}}