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Define P1, P2, and P3 to be the polynomials
Now define Q1 to be the product of P1 and P2 and Q2 to be the product of P1 and P3, and use
greatest-common-divisor (exercise 2.94) to compute the GCD of Q1 and Q2. Note that the answer is not the same as P1. This example introduces noninteger operations into the computation, causing difficulties with the GCD algorithm. To understand what is happening, try tracing
gcd-terms while computing the GCD or try performing the division by hand.