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If A=[[cosalpha,-sinalpha,0],[sinalpha,c...

If `A=[[cosalpha,-sinalpha,0],[sinalpha,cosalpha,0],[0, 0, 1]]` find `a d j` and verify that `A(a d jA)=(a d jA)A=|A|I_3`

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Given that,
`A=[[cosalpha,-sinalpha,0],[sinalpha,cosalpha,0],[0, 0, 1]]` Let `c_ij` be cofactors of matrix `A`
`c_11 =[[cos alpha, 0],[0, 1]]=cos alpha`
`c_12 =-[[sin alpha,0],[0, 1]]=-sin alpha`
`c_13 =[[sin alpha, cos alpha],[0, 0]]=0`
`c_21 =-[[sin alpha , 0],[0, 1]]=-sin alpha`
`c_22 =[[cos alpha , 0],[0, 1]]=cos alpha`
...
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