If is a root of , then also a root. Thus and are factors of . Divide by , and then you will get the quadric By plugging in possible integer roots, find that yields the quadric zero, so is a factor of it. Divide the quadric by , and you will get . Keep going like this and find the roots of the cubic. Writing the equation as the product of linear factors means writing [LaTeX ERROR: Convert failed] as , where , , , , , and are the roots you were asked to find, of which we already have three: , , and , and the other three are the roots of the cubic .