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The first equation is PQR.

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$\"\"$ $\"\"$

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Substitute matrix R. \ \

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$\"\"$ (Multiply columns by rows)

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$\"\"$ (Simplify) $\"\"$

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The second equation is RQP.

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$\"\"$ (Simplify) $\"\"$ \ \

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$\"\"$ (Substitute matrix P)

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Multiply columns by rows.

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$\"\"$ (Simplify) $\"\"$

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The solution of equation PQR = RQP is True.