Using the remainder theorem, factorise each of the following completely :

3x³ + 2x² - 19x + 6

Using the remainder theorem, factorise each of the following completely :

2x³ + x² - 13x + 6

Using the remainder theorem, factorise each of the following completely :

4x³ + 7x² - 36x - 63

Using the remainder theorem, factorise each of the following completely :

x³ + x² - 4x - 4