Question

Difference of Squares gives which complex factors for the expression x² +11?

A. (x+√11)2(x-i√11)²
B. (x+√11)(x+√11)
C. (x-i√11)(x-√11)
D. (x+√11)(x - √11)

Answer 1

Explanation:

Discussion

i has to appear somewhere. That lets D and B out. They are both wrong.

C has only one i. It can't be right either. You need 2 i-s which will multiply to +1 when squared. That leaves you with a.

The way a is written, it can't be the answer either. For one thing, that 2 makes the answer question at best.

I would say there is no correct answer. Could you check the question? Also it would be a good idea to ask your instructor how this works, in case I'm wrong.