Question

The side length, s, of a cube is 4x^2+3. If V=s^3, what is the volume of the cube?

Answer 1

The volume of the cube is $(4x^{2} +3)(4x^{2} +3)(4x^{2} +3)$.

To simplify this, use the FOIL method between the first two terms, and then the product and the last term:

$(4x^{2} +3)(4x^{2} +3)(4x^{2} +3)\\(16x^{4}+12x^{2} +12x^{2} +9)(4x^{2} +3)\\(16x^{4}+24x^{2} +9)(4x^{2} +3)\\(64x^{6}+48x^{4} +96x^{4}+72x^{2} +36x^{2}+27)\\ 64x^{6}+144x^{4}+108x^{2} +27$

The answer is the first choice.

Hope this helps!!