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Given A=[(4,2,5),(2,0,3),(-1,1,0)] wri...

Given `A=[(4,2,5),(2,0,3),(-1,1,0)]` write the value of det. `("2AA"^(-1))` .

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To find the value of \( \text{det}(2AA^{-1}) \), we can follow these steps: ### Step 1: Understand the properties of determinants We know that for any square matrix \( A \): \[ \text{det}(AA^{-1}) = \text{det}(I) = 1 \] where \( I \) is the identity matrix. ### Step 2: Use the property of determinants with scalar multiplication The determinant of a scalar multiple of a matrix can be expressed as: \[ \text{det}(kA) = k^n \cdot \text{det}(A) \] where \( n \) is the order (dimension) of the square matrix \( A \) and \( k \) is a scalar. ### Step 3: Apply the properties to our problem In our case, we need to find: \[ \text{det}(2AA^{-1}) = \text{det}(2I) \] Since \( AA^{-1} = I \). ### Step 4: Calculate the determinant of \( 2I \) For a \( 3 \times 3 \) identity matrix \( I \): \[ I = \begin{pmatrix} 1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1 \end{pmatrix} \] Multiplying by 2 gives: \[ 2I = \begin{pmatrix} 2 & 0 & 0 \\ 0 & 2 & 0 \\ 0 & 0 & 2 \end{pmatrix} \] ### Step 5: Calculate the determinant of \( 2I \) Using the property of determinants: \[ \text{det}(2I) = 2^3 \cdot \text{det}(I) = 2^3 \cdot 1 = 8 \] ### Final Answer Thus, the value of \( \text{det}(2AA^{-1}) \) is: \[ \boxed{8} \]
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