# How do you factor 2x^3+54?

Dec 24, 2015

$2 {x}^{3} + 54 = 2 \left(x + 3\right) \left({x}^{2} - 3 x + 9\right)$
$2 \left({x}^{3} + 27\right)$
Then recognize this as the sum of cubes. To factor cubes, memorize the expression a^3 + b^3 = (a + b)(a^2 – ab + b^2)
Then $2 {x}^{3} + 54 = 2 \left(x + 3\right) \left({x}^{2} - 3 x + 9\right)$