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If [[2, 1], [3, 2]]A[[-3, 2], [5, -3]]=[...

If `[[2, 1], [3, 2]]A[[-3, 2], [5, -3]]=[[1, 0], [0, 1]]`, then A=

A

`[[1, 1], [1,0]]`

B

`[[1, 0], [1, 1]]`

C

`[[0, 1], [1, 1]]`

D

0

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To solve the equation \( [[2, 1], [3, 2]] A [[-3, 2], [5, -3]] = [[1, 0], [0, 1]] \), we will follow these steps: ### Step 1: Define the matrices Let: - \( B = [[2, 1], [3, 2]] \) - \( C = [[-3, 2], [5, -3]] \) - \( I = [[1, 0], [0, 1]] \) (identity matrix) The equation can be rewritten as: \[ B A C = I \] ### Step 2: Pre-multiply by \( B^{-1} \) and post-multiply by \( C^{-1} \) To isolate \( A \), we will pre-multiply both sides by \( B^{-1} \) and post-multiply by \( C^{-1} \): \[ B^{-1} (B A C) C^{-1} = B^{-1} I C^{-1} \] This simplifies to: \[ A = B^{-1} I C^{-1} = B^{-1} C^{-1} \] ### Step 3: Calculate \( B^{-1} \) To find \( B^{-1} \), we first calculate the determinant of \( B \): \[ \text{det}(B) = (2)(2) - (1)(3) = 4 - 3 = 1 \] Since the determinant is non-zero, \( B \) is invertible. The formula for the inverse of a \( 2 \times 2 \) matrix \( [[a, b], [c, d]] \) is: \[ \frac{1}{ad - bc} [[d, -b], [-c, a]] \] Applying this to matrix \( B \): \[ B^{-1} = \frac{1}{1} [[2, -1], [-3, 2]] = [[2, -1], [-3, 2]] \] ### Step 4: Calculate \( C^{-1} \) Next, we calculate the determinant of \( C \): \[ \text{det}(C) = (-3)(-3) - (2)(5) = 9 - 10 = -1 \] Since the determinant is non-zero, \( C \) is also invertible. Using the inverse formula: \[ C^{-1} = \frac{1}{-1} [[-3, -2], [5, -3]] = [[3, 2], [-5, 3]] \] ### Step 5: Calculate \( A \) Now we can find \( A \) by multiplying \( B^{-1} \) and \( C^{-1} \): \[ A = B^{-1} C^{-1} = [[2, -1], [-3, 2]] [[3, 2], [-5, 3]] \] ### Step 6: Perform the multiplication Calculating the product: \[ A_{11} = 2 \cdot 3 + (-1) \cdot (-5) = 6 + 5 = 11 \] \[ A_{12} = 2 \cdot 2 + (-1) \cdot 3 = 4 - 3 = 1 \] \[ A_{21} = -3 \cdot 3 + 2 \cdot (-5) = -9 - 10 = -19 \] \[ A_{22} = -3 \cdot 2 + 2 \cdot 3 = -6 + 6 = 0 \] Thus, we have: \[ A = [[11, 1], [-19, 0]] \] ### Step 7: Check the options The options provided were: 1. \( [[1, 1], [1, 0]] \) 2. \( [[1, 0], [1, 1]] \) 3. \( [[0, 1], [1, 1]] \) 4. Null matrix None of the options match the calculated matrix \( A \). ### Conclusion The value of \( A \) is: \[ A = [[11, 1], [-19, 0]] \]
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