# How do you determine the binomial factors of x^3+x^2-4x-4?

##### 1 Answer
Jul 19, 2017

$= \left(x + 1\right) \left(x + 2\right) \left(x - 2\right)$

#### Explanation:

Group the four terms into two pairs, making sure there is a + sign between them. Then take out a common factor from each.

$\left({x}^{3} + {x}^{2}\right) + \left(- 4 x - 4\right)$

$= {x}^{2} \left(x + 1\right) - 4 \left(x + 1\right) \text{ } \leftarrow$ note the change in signs!

There is a common bracket in the two terms:

$= \left(x + 1\right) \left({x}^{2} - 4\right) \text{ } \leftarrow$ factor the difference of squares

$= \left(x + 1\right) \left(x + 2\right) \left(x - 2\right)$