How do you factor 8u^3+278u3+27?

1 Answer
Jan 5, 2016

8u^3+27=(2u+3)(4u^2-6u+9)8u3+27=(2u+3)(4u26u+9)

Explanation:

8u^3+278u3+27

Since 8u^38u3 and 2727 are cubes, we can rewrite the expression as (2u)^3+(3)^3(2u)3+(3)3.

This a sum of two cubes with the form a^3+b^3=(a+b)(a^2-ab+b^2)a3+b3=(a+b)(a2ab+b2), where a=2ua=2u and b=3b=3.

Substitute the values for aa and bb into the equation.

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

Simplify.

(2u)^3+(3)^3=(2u+3)(4u^2-6u+9)(2u)3+(3)3=(2u+3)(4u26u+9)