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A and B are two matrices of same order 3...

A and B are two matrices of same order `3 xx 3`, where `A=[{:(1,2,3),(2,3,4),(5,6,8):}],B=[{:(3,2,5),(2,3,8),(7,2,9):}]` Value of |adj (adj adj( adj A)))| is

A

`2^4`

B

`2^9`

C

`1`

D

`2^19`

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To find the value of \(|\text{adj}(\text{adj}(\text{adj}(\text{adj} A)))|\), we will follow these steps: ### Step 1: Calculate the Determinant of Matrix A Given the matrix \( A = \begin{pmatrix} 1 & 2 & 3 \\ 2 & 3 & 4 \\ 5 & 6 & 8 \end{pmatrix} \), we need to find the determinant \(|A|\). Using the determinant formula for a \(3 \times 3\) matrix: \[ |A| = a(ei - fh) - b(di - fg) + c(dh - eg) \] where \( A = \begin{pmatrix} a & b & c \\ d & e & f \\ g & h & i \end{pmatrix} \). For our matrix: - \( a = 1, b = 2, c = 3 \) - \( d = 2, e = 3, f = 4 \) - \( g = 5, h = 6, i = 8 \) Calculating the determinant: \[ |A| = 1(3 \cdot 8 - 4 \cdot 6) - 2(2 \cdot 8 - 4 \cdot 5) + 3(2 \cdot 6 - 3 \cdot 5) \] \[ = 1(24 - 24) - 2(16 - 20) + 3(12 - 15) \] \[ = 1(0) - 2(-4) + 3(-3) \] \[ = 0 + 8 - 9 \] \[ = -1 \] ### Step 2: Use the Property of Determinants of Adjoint Matrices The property of determinants states that: \[ |\text{adj}(A)| = |A|^{n-1} \] where \( n \) is the order of the matrix. For a \(3 \times 3\) matrix, \( n = 3 \). Thus: \[ |\text{adj}(A)| = |A|^{3-1} = |A|^2 = (-1)^2 = 1 \] ### Step 3: Calculate the Determinant of the Adjoint of the Adjoint Now, we need to find \(|\text{adj}(\text{adj}(A))|\): \[ |\text{adj}(\text{adj}(A))| = |\text{adj}(A)|^{3-1} = |A|^{(3-1)(3-1)} = |A|^{2} = 1^2 = 1 \] ### Step 4: Calculate the Determinant of the Adjoint of the Adjoint of the Adjoint Next, we find \(|\text{adj}(\text{adj}(\text{adj}(A)))|\): \[ |\text{adj}(\text{adj}(\text{adj}(A)))| = |\text{adj}(\text{adj}(A))|^{3-1} = |A|^{(3-1)(3-1)} = |A|^{2} = 1^2 = 1 \] ### Step 5: Calculate the Determinant of the Adjoint of the Adjoint of the Adjoint of the Adjoint Finally, we find \(|\text{adj}(\text{adj}(\text{adj}(\text{adj}(A))))|\): \[ |\text{adj}(\text{adj}(\text{adj}(\text{adj}(A))))| = |\text{adj}(\text{adj}(\text{adj}(A)))|^{3-1} = |A|^{(3-1)(3-1)} = |A|^{2} = 1^2 = 1 \] ### Conclusion Thus, the value of \(|\text{adj}(\text{adj}(\text{adj}(\text{adj}(A))))|\) is \( \boxed{1} \).
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