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Question
Find the adjoint of the matrices.
`[(1,2),(3,4)]`
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Solution
Here A = `[(1,2),(3,4)]` then
adj A = `[(A_11, A_12),(A_21, A_22)]^T`
`= [(4,-3),(-2,1)]^T ...[(A_11 = 4, A_12 = - 3),(A_21 = - 2, A_22 = 1)]`
`= [(4,-2),(-3,1)]`
Hence, adjoint matrix of `[(1,2),(3,4)]` = `[(4,-2),(-3,1)]`
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