posted by julez .
Find the real and complex zeros of the following function.
x = -1 is one root, as you can easily verify by inspection. That means that (x +1) is a factor of the polynomial.
Divide x^3-3x^2+25x+29 by x+1 (using polynomial long division) to get a second order polynomial, from which you can get the other roots easily, using the quadratic formula. They will be complex in this case.