WEBVTT

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Here is the problem: A minus B: A equals [[1, 2], [3, 4]].

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Compute A minus B exactly.

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Read matrix A.

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Read matrix B.

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Subtract matching entries.

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Result.

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So the answer is A minus B equals [[-3, negative 1], [1, 3]].

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Addition and subtraction work entry by entry and require matrices of the same size.

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All arithmetic is exact (fractions, no rounding).