Question

If the complex solutions of x^4-x^2-2=0 are A and B, what is AB?

Answer 1

1.

Explanation:

x^4-x^2-2=0

(x^2)^2 - x^2 - 2 = 0

(x^2 - 2)(x^2 + 1) = 0

x^2 = 2 or x^2 = -1

The complex roots are +/-√-1

= i , -i

So, AB - i * i

= -i^2

= -(-1)

= 1.