Question

Why is my answer wrong?? (comments)

Answer 1

have you tried plugging in the roots to see if they work?

Answer 2

your terms look good except you have some positive/negative issues going on

Answer 3

No, I didn't try that. How so? I took into account the whol i^2=-1, that seemed like the only thing to keep an eye on.

Answer 4

lets give it a shot

(x+2i)(x-2i) = x^2 + 4

x^2 + 4
x + 1
---------
x^3 +4x
+x^2 +4
---------------
\(x^3+x^2+4x+4\)

Answer 5

im sure you did a rather simple mistake ... it happens :)

Answer 6

I see...thank you for your explanation :)

Answer 7

good luck