Choose one of the factors of x3 – 1331

x – 11

x2 – 11x + 121

x2 + 22x + 121

None of the above

This is about the sum or difference in cubs (factoring) and I'm pretty sure it's "none of the above." could anyone double check?

Question

Choose one of the factors of x3 – 1331 

 x – 11 

 x2 – 11x + 121 

 x2 + 22x + 121 

 None of the above 

This is about the sum or difference in cubs (factoring) and I'm pretty sure it's "none of the above." could anyone double check?

anonymous · Answer

cubes*

lgbasallote · Answer

hint 1331 = 11^3

anonymous · Answer

I did the work already, but think it's wrong @lgba.

lgbasallote · Answer

therefore you can use difference of two cubes

a^3 - b^3 = (a-b)(a^2 + ab + b^2)

lgbasallote · Answer

a = x and b = 11

anonymous · Answer

(x-11)(x^2+11x+121) Would this be correct?

lgbasallote · Answer

yup

lgbasallote · Answer

so is the answer obvious now? :D

anonymous · Answer

Oh okay tyvm, I didn't know it the addition signs in the 2nd one would turn to subtraction cause of the -11. Thx :) and yeah it's really easy :) All you need to know is the formula thingie you posted above :)

lgbasallote · Answer

yup..the formula for cubes is sometimes tricky in my opinion haha

anonymous · Answer

i still dont get it