# How do you factor #F(x)= -x^4 + 2x^3 + 4x^2 - 8x#?

##### 1 Answer

Aug 3, 2015

#### Explanation:

Notice that you can group the first two terms and the second two terms together and factor them to get

You can factor these two terms by

Notice that you can factor the second term of the expression by

Finally, you can factor *difference of two squares*

#color(blue)(a^2 - b^2 = (a-b)(a+b))#

In your case, you have

The expression will now become

which is equivalent to