We may use the rational root theorem: The rational zeros of a polynomial
(if they exist) will be of the form:
So, for example, the possible rational zeros of the numerator are . I find that both x = -1 and x = -2 are zeros of the polynomial. Thus
We can find the remaining zero by long division, synthetic division, or by multiplying the above factorized expression out and solving for p. I get:
You can do a similar factorization of the denominator.