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Rational Roots (C)

Suppose that all the coefficients of a polynomial p(z) are integers. If m and n are integers with no common factors and p(m/n) = 0 then m divides the constant term in p and n divides the leading coeficient.

Observe that every polynomial with rational coeffients is a polynomial with integer coefficients divided by a fixed integer, namely the least common multiple of its coefficients.

Exercises List all the possible rational roots of

1.
z9 + 6z + 6;
2.
z12 -44z3 - 12;
3.
4z4 + 9z - 2;
4.
(4/3)z9 + 6z2 + 11;


Eric S Key
5/8/2001