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Let A=[a(ij)](5xx5) is a matrix such tha...

Let `A=[a_(ij)]_(5xx5)` is a matrix such that `a_(ij)={(3,AA i= j),(0,Aai ne j):}`. If `|(adj(adjA))/(3)|=(sqrt3)^(lambda),` then `lambda` is equal to (where, `adj(M)` represents the adjoint matrix of matrix M)

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To solve the problem, we need to analyze the given matrix \( A \) and find the value of \( \lambda \) such that \[ \left| \frac{\text{adj}(\text{adj}(A))}{3} \right| = (\sqrt{3})^{\lambda}. \] ### Step 1: Define the matrix \( A \) The matrix \( A \) is a \( 5 \times 5 \) diagonal matrix where the diagonal entries are all \( 3 \) and all off-diagonal entries are \( 0 \). Thus, we can write: \[ A = \begin{bmatrix} 3 & 0 & 0 & 0 & 0 \\ 0 & 3 & 0 & 0 & 0 \\ 0 & 0 & 3 & 0 & 0 \\ 0 & 0 & 0 & 3 & 0 \\ 0 & 0 & 0 & 0 & 3 \end{bmatrix}. \] ### Step 2: Calculate the determinant of \( A \) The determinant of a diagonal matrix is the product of its diagonal entries. Therefore, \[ |A| = 3 \times 3 \times 3 \times 3 \times 3 = 3^5. \] ### Step 3: Use the property of the adjoint The property of the adjoint states that: \[ |\text{adj}(A)| = |A|^{n-1}, \] where \( n \) is the order of the matrix. For our \( 5 \times 5 \) matrix \( A \), \[ |\text{adj}(A)| = |A|^{5-1} = |A|^4 = (3^5)^4 = 3^{20}. \] ### Step 4: Calculate the adjoint of the adjoint Now, we need to find \( |\text{adj}(\text{adj}(A))| \). Using the same property again: \[ |\text{adj}(\text{adj}(A))| = |\text{adj}(A)|^{n-1} = (3^{20})^{5-1} = (3^{20})^4 = 3^{80}. \] ### Step 5: Divide by 3 and equate to \( (\sqrt{3})^{\lambda} \) Now we need to calculate: \[ \left| \frac{\text{adj}(\text{adj}(A))}{3} \right| = \frac{|\text{adj}(\text{adj}(A))|}{|3|} = \frac{3^{80}}{3} = 3^{79}. \] ### Step 6: Set up the equation We need to equate this to \( (\sqrt{3})^{\lambda} \): \[ 3^{79} = (\sqrt{3})^{\lambda} = 3^{\lambda/2}. \] ### Step 7: Solve for \( \lambda \) Equating the exponents gives us: \[ 79 = \frac{\lambda}{2}. \] Multiplying both sides by \( 2 \): \[ \lambda = 158. \] ### Final Answer Thus, the value of \( \lambda \) is \[ \boxed{158}. \]
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