Factories:
x3 – 3x2 + x – 3
= (x3 – 3x2) + (x -3)
= x2(x – 3) + 1(x – 3)
= (x – 3)(x2 + 1)
So we get,
x3 – 3x2 + x – 3 = (x – 3)(x2 + 1)