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If A is a square matrix of order 3 such ...

If `A` is a square matrix of order 3 such that `|A|=2,t h e n|(a d jA^(-1))^(-1)|` is ___________.

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To solve the problem, we need to find the value of \(|(adj A^{-1})^{-1}|\) given that \(|A| = 2\) and \(A\) is a square matrix of order 3. ### Step-by-step Solution: 1. **Understanding the Determinant of the Adjoint**: We know that for any square matrix \(A\), the determinant of the adjoint of \(A\) is given by: \[ |adj A| = |A|^{n-1} \] where \(n\) is the order of the matrix. Since \(A\) is a \(3 \times 3\) matrix, \(n = 3\). Therefore, \[ |adj A| = |A|^{3-1} = |A|^2 \] 2. **Finding the Determinant of \(A^{-1}\)**: The determinant of the inverse of a matrix is given by: \[ |A^{-1}| = \frac{1}{|A|} \] Given \(|A| = 2\), we have: \[ |A^{-1}| = \frac{1}{2} \] 3. **Finding the Determinant of the Adjoint of \(A^{-1}\)**: Now, we can find the determinant of the adjoint of \(A^{-1}\): \[ |adj A^{-1}| = |A^{-1}|^{3-1} = |A^{-1}|^2 \] Substituting \(|A^{-1}| = \frac{1}{2}\): \[ |adj A^{-1}| = \left(\frac{1}{2}\right)^2 = \frac{1}{4} \] 4. **Finding the Determinant of \((adj A^{-1})^{-1}\)**: The determinant of the inverse of a matrix is the reciprocal of the determinant of the matrix. Therefore: \[ |(adj A^{-1})^{-1}| = \frac{1}{|adj A^{-1}|} = \frac{1}{\frac{1}{4}} = 4 \] ### Final Answer: Thus, the value of \(|(adj A^{-1})^{-1}|\) is \(4\). ---

To solve the problem, we need to find the value of \(|(adj A^{-1})^{-1}|\) given that \(|A| = 2\) and \(A\) is a square matrix of order 3. ### Step-by-step Solution: 1. **Understanding the Determinant of the Adjoint**: We know that for any square matrix \(A\), the determinant of the adjoint of \(A\) is given by: \[ |adj A| = |A|^{n-1} ...
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