posted by Caylan on .
use the rational zeros theorem to find all the real zeros of the polynomial. Use the zeros to factor f over the real numbers.
One root is x = 1/2, so one factor is x - 1/2
Divide f(x) by x - 1/2 to yield a quadratic equation
2x^2 + x +2 = 0
that will provide the other two roots.