p(x) = (x + 1)(x - 2), x = - 1, 2p(- 1) = (-1 + 1)(- 1 - 2)= (0)(- 3)= 0p(2) = (2 + 1)(2 - 2) = (3)(0) = 0∴ -1, 2 are zeros of p(x).