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Question
If A = `[(2, 0),(0, 1)]` and B = `[(1),(2)]`, then find the matrix X such that A−1X = B.
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Solution
A–1X = B
∴ A(A–1X) = AB
∴ (AA–1)X = AB
∴ IX = AB
∴ X = `[(2, 0),(0, 1)][(1),(2)] = [(2 + 0),(0 + 2)]`
∴ X = `[(2),(2)]`.
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