r(x) = –x² + 3x s(x) = 2x + 1(s – r)(x) =

Subtract r(x) from s(x): (s − r)(x) = (2x + 1) − (−x² + 3x). This matches choice C, and simplifying gives x² − x + 1. The subtraction changes the signs of both terms in r(x).

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