# How do you factor #x^4-8x^2+16#?

##### 3 Answers

#### Explanation:

Make a dumby variable, in this case I will use

Let

You have

This is equivalent to

You can now plug in

You get

Now, you can factor this like a normal polynomial.

or

Finally, you plug in

The factored form will be

#### Explanation:

Notice how this is almost a simple quadratic trinomial. In fact, it can be thought of as a quadratic of

Let

We can easily factor this quadratic.