1/ = x4 + 2x3 + 4x2 + 3x - 10 = (x4 - x3) + (3x3 - 3x2) + (7x2 - 7x) + (10x - 10)
= (x - 1)(x3 + 3x2 + 7x + 10) = (x - 1)[(x3 + 2x2) + (x2 + 2x) + (5x + 10)]
= (x - 1)(x + 2)(x2 + x + 5)
2/ = (x5 - 2x4) + (x4 - 2x3) + (x3 - 2x2) + (x2 - 2x) + (x - 2) = (x - 2)(x4 + x3 + x2 + x + 1)