SICP Exercise 2.96 pseudoremainder

Exercise 2.96.

a.    Implement the procedure pseudoremainder-terms, which is just like remainder-terms except that it multiplies the dividend by the integerizing factor described above before calling div-terms. Modify gcd-termsto use pseudoremainder-terms, and verify that greatest-common-divisor now produces an answer with integer coefficients on the example in exercise 2.95.

b.    The GCD now has integer coefficients, but they are larger than those of P1. Modify gcd-terms so that it removes common factors from the coefficients of the answer by dividing all the coefficients by their (integer) greatest common divisor.

SOLUTION

 The code is here:


Both part a and b of the exercise are verified in the tests. The final result is equal to polynomial P1 from exercise 2.95.

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