Factor the expression completely over the complex numbers. x3−4x2+4x−16 enter your answer in the box.

(x-4)  (x-2i) (x+2i)

Step-by-step explanation:

x^3−4x^2+4x−16

I will factor by grouping

x^3−4x^2+  4x−16

The first group is the first 2 terms.  I can factor out an x^2

x^2 (x-4) + 4x-16

The second group I can factor out a 4

x^2 (x-4) + 4(x-4)

Now I can factor out (x-4)

(x-4)  (x^2 +4)

We know that x^2 + 4 factors into +2i and -2i  because

(a^2 -b^2) = (a-b) (a+b)  but  we have (a^2 + b^2)  = (a-bi)  (a+bi)

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

step-by-step explanation:

it's is b