Verified answer

P(x)/D(x) = Q(x) + R(x)/D(x)

P(x) = Q(x)*D(x) + R(x)

P(1) = Q(1)*D(1) + R(1)

P(x) = (x³ - 2x - 1)*D(x) + 5x + 8

P(1) = (1 - 2 - 1)*D(1) + 13

P(1) = -2*D(1) + 13

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