#1**+2 **

To have real coeeficients there has to be a - i root also

Quadratic formula:

\(x = {-b \pm \sqrt{b^2-4ac} \over 2a}\)

shows that to have an i root the discriminant has to be NEGATIVE...and the disriminant is a + or - term....so there will be ANOTHER -2i root to go with the +2 i root

ElectricPavlov Feb 19, 2019