# How do you factor the expression 18x²-2?

$2 \left(3 x - 1\right) \left(3 x + 1\right)$
First take out the common factor, giving $2 \left(9 {x}^{2} - 1\right)$
Then recognize this as the difference of two squares and use the fact that $\left({m}^{2} - {n}^{2}\right)$ factors as$\left(m - n\right) \left(m + n\right)$ to get
$2 \left(3 x - 1\right) \left(3 x + 1\right)$