How do you factor 8u^3+27?

1 Answer
Jan 5, 2016

8u^3+27=(2u+3)(4u^2-6u+9)

Explanation:

8u^3+27

Since 8u^3 and 27 are cubes, we can rewrite the expression as (2u)^3+(3)^3.

This a sum of two cubes with the form a^3+b^3=(a+b)(a^2-ab+b^2), where a=2u and b=3.

Substitute the values for a and b into the equation.

(2u)^3+(3)^3=(2u+3)(2u)^2-(2u)(3)+(3)^2

Simplify.

(2u)^3+(3)^3=(2u+3)(4u^2-6u+9)