Note: Make sure to fully factor each of the below. Remember that, factor by grouping is just one step in the factoring process, you should check any resulting factors you get after factor by grouping (or any other factoring method) to see if they are still factorable.

1 : Factor the following polynomial:
2 : Factor the following polynomial:
3 : Factor the following polynomial:
4 : Factor the following polynomial:
5 : Factor the following polynomial: