a) 4.x^3 - 7.x^2 - x - 2
= (4.x^3 - 8.x^2) + (x^2 - 2x) + (x - 2)
= (x - 2)(4.x^2 + x + 1)
Vậy 4.x^3 - 7.x^2 - x - 2 chia hết cho x - 2

b) 4.x^3 - 7.x^2 - x - 2
= (4.x^3 + 8.x^2) - (15.x^2 + 30x) + (29x + 58) - 60
= (x + 2)(4.x^2 - 15x + 29) - 60
Vậy 4.x^3 - 7.x^2 - x - 2 không chia hết cho x + 2