Is g (x) = (x-1) (x+1) (x-3i) (x+3i) the factored form of f (x) = x^4+8x^2-9

Question

Frosty

Mathematics

29 January, 04:43

Is g (x) = (x-1) (x+1) (x-3i) (x+3i) the factored form of f (x) = x^4+8x^2-9

+2

Answers (1)

Know the Answer?

Karla Gaines · Answer 1

Yes

Step-by-step explanation:

(x-1) (x+1) (x-3i) (x+3i)

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

FOIL (x-3i) (x+3i) = x^2 + 3ix - 3ix - 9i^2 = x^2 - 9 (-1) = x^2 + 9

(x-1) (x+1) (x-3i) (x+3i) = (x^2 - 1) (x^2 + 9)

FOIL again

x^4 + 9x^2 - x^2 - 9

x^2 + 8x^2 - 9

This is the factored form