list all the possible integral zeros:

P(x)= x^3-2x^2-11x+12

1 answer

The factor theorem helps us to say that the possible integral roots are in the form of (x±k), where k is a possible factor of the constant term (12) divided by a possible factor of the leading coefficient (1).
Thus for the given problem, the possible integral zeroes are
±1,±2,±3,±4,±6,±12.

Also, the sign of the coefficients changed twice, so by Descartes rule of signs, there are zero or two positive roots, and one negative root.