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If A=1/9[[-8, 1 ,4], [ 4, 4, 7], [ 1, -8...

If `A=1/9[[-8, 1 ,4], [ 4, 4, 7], [ 1, -8, 4]]` , prove that `A^(-1)=A^T` .

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`A=1/9[[-8, 1 ,4], [ 4, 4, 7], [ 1, -8, 4]]`
`A A^(-1)=I`
`A A^T=I=>A^T=A^(-1)`
`A^T=1/9 [[-8, 1 ,4], [ 4, 4, 7], [ 1, -8, 4]]`
`A A^T=1/9 [[-8, 1 ,4], [ 4, 4, 7], [ 1, -8, 4]] 1/9 [[-8, 4, 1], [1, 4, -8], [4, 7, 4]]`
`= 1/81 [[81, 0, 0], [0, 81, 0], [0, 0, 81]]`
`=[[1, 0, 0], [0, 1, 0], [0, 0, 1]]`
`A A^T=I` ...
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