# How do you factor the expression 3x^3+3x^2+x+1?

Mar 8, 2016

$\left(3 {x}^{2} + 1\right) \left(x + 1\right)$

#### Explanation:

Factor by grouping--split into two groups of two.

$= \left(3 {x}^{3} + 3 {x}^{2}\right) + \left(x + 1\right)$

$= 3 {x}^{2} \left(x + 1\right) + 1 \left(x + 1\right)$

$= \left(3 {x}^{2} + 1\right) \left(x + 1\right)$

This is completely factored, if we refrain from using complex numbers.