Which of the following expressions is equal to 2x^ (2) + 8?

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

(2x-4i) (x-2i)

(2x+4i) (x+2i)

(2x-2i) (x+6i)

The expression equal to 2x^ (2) + 8 is:

First option (2x-4i) (x+2i)

Step-by-step explanation:

If we multiply

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

(2x-4i) (x+2i) = 2x^ (1+1) + 4xi-4xi-8i^ (1+1)

Simplifying:

(2x-4i) (x+2i) = 2x^2-8i^2

and i^2=-1, then:

(2x-4i) (x+2i) = 2x^2-8 (-1)

Multiplying:

(2x-4i) (x+2i) = 2x^2+8