Question

Which of the following polynomials does not have real roots?

A. 2x2 - 13
B. x2 - 17x - 7
C. x4 + 2x2 + 2
D. -x4 + 4x2 + 6

Answer 1

Have you tried using the discriminant: \(\large b^2 - 4ac\)

Answer 2

C.\[\left\{x=\pm \sqrt{-1-i},x=\pm \sqrt{-1+i}\right\} \]

Answer 3

Yah, that looks good.