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If A+B=[(1,0,2),(2,2,2),(1,1,2)] and A-B...

If `A+B=[(1,0,2),(2,2,2),(1,1,2)]` and `A-B=[(1,4,4),(4,2,0),(-1,1,2)]` then `A=[(1,2,3),(3,2,1),(0,0,2)]` and `B=[(0,-2,-1),(-1,0,1),(1,1,0)]`

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To solve the problem, we need to find the matrices A and B given the equations: 1. \( A + B = \begin{pmatrix} 1 & 0 & 2 \\ 2 & 2 & 2 \\ 1 & 1 & 2 \end{pmatrix} \) 2. \( A - B = \begin{pmatrix} 1 & 4 & 4 \\ 4 & 2 & 0 \\ -1 & 1 & 2 \end{pmatrix} \) ### Step 1: Add the two equations We will add the two equations together: \[ (A + B) + (A - B) = \begin{pmatrix} 1 & 0 & 2 \\ 2 & 2 & 2 \\ 1 & 1 & 2 \end{pmatrix} + \begin{pmatrix} 1 & 4 & 4 \\ 4 & 2 & 0 \\ -1 & 1 & 2 \end{pmatrix} \] This simplifies to: \[ 2A = \begin{pmatrix} 1 + 1 & 0 + 4 & 2 + 4 \\ 2 + 4 & 2 + 2 & 2 + 0 \\ 1 - 1 & 1 + 1 & 2 + 2 \end{pmatrix} \] Calculating each element: \[ 2A = \begin{pmatrix} 2 & 4 & 6 \\ 6 & 4 & 2 \\ 0 & 2 & 4 \end{pmatrix} \] ### Step 2: Divide by 2 to find A Now, we divide each element by 2 to find matrix A: \[ A = \frac{1}{2} \begin{pmatrix} 2 & 4 & 6 \\ 6 & 4 & 2 \\ 0 & 2 & 4 \end{pmatrix} = \begin{pmatrix} 1 & 2 & 3 \\ 3 & 2 & 1 \\ 0 & 0 & 2 \end{pmatrix} \] ### Step 3: Substitute A back to find B Now that we have A, we can substitute it back into one of the original equations to find B. We'll use the first equation: \[ B = (A + B) - A \] Substituting the values: \[ B = \begin{pmatrix} 1 & 0 & 2 \\ 2 & 2 & 2 \\ 1 & 1 & 2 \end{pmatrix} - \begin{pmatrix} 1 & 2 & 3 \\ 3 & 2 & 1 \\ 0 & 0 & 2 \end{pmatrix} \] Calculating B: \[ B = \begin{pmatrix} 1 - 1 & 0 - 2 & 2 - 3 \\ 2 - 3 & 2 - 2 & 2 - 1 \\ 1 - 0 & 1 - 0 & 2 - 2 \end{pmatrix} = \begin{pmatrix} 0 & -2 & -1 \\ -1 & 0 & 1 \\ 1 & 1 & 0 \end{pmatrix} \] ### Final Matrices Thus, we have: \[ A = \begin{pmatrix} 1 & 2 & 3 \\ 3 & 2 & 1 \\ 0 & 0 & 2 \end{pmatrix} \] \[ B = \begin{pmatrix} 0 & -2 & -1 \\ -1 & 0 & 1 \\ 1 & 1 & 0 \end{pmatrix} \]
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Knowledge Check

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    A
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    A
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    B
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    C
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    D
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    A
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    B
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    C
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    D
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