Question

Choose one of the factors of 1331x^3 – 8y^3
Answer
121x^2 + 44xy + 4y^2
121x^2 – 22xy + 4y^2
4
11x – 2y

Answer 1

Knowing that
1331x^3 – 8y^3 = (11x)^3-(2y)^3, and
from A^3-B^3=(A-B)(A^2+AB+B^2)
you can eliminate the second and third.
Check the first one just to be sure.