How do you factor #b^3 + 27#?

1 Answer
Feb 3, 2016

#b^3+27=(b+3)(b^2-3b+9)#

Explanation:

#b^3+27# is an example of a sum of cubes, where #a=b# and #b=3.#. Rewrite the expression as #(b)^3+(3)^3#.

To solve the sum of cubes, use the equation #a^3+b^3=(a+b)(a^2-ab+b^2)#.

Substitute the values for #a and b# into the equation.

#(b)^3+(3)^3=(b+3)(b^2-(b)(3)+3^2)#

Simplify.

#(b)^3+(3)^3=(b+3)(b^2-3b+9)#