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If A = [2001] and B = [12], then find the matrix X such that A−1X = B.

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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.

Sum
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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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Chapter 1.2: Matrics - Short Answers I

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