Question

x3 - x2 - 4x + 4 = 0

Answer 1

$x^3-x^2-4x+4=0\\\\x^2(x-1)-4(x-1)=0\\\\(x-1)\left[x^2-4\right]=0\\\\(x-1)(x+2)(x-2)=0\\\\\boxed{S=\left\{-2,1,2\right\}}$