Question 202436
{{{(x+2y)^3}}} Start with the given expression.



{{{(x+2y)(x + 2y)^2}}} Factor 



{{{(x+2y)(x^2+4xy+4y^2)}}} FOIL



{{{x(x^2+4xy+4y^2)+2y(x^2+4xy+4y^2)}}} Expand



{{{x^3+4x^2*y+4xy^2+2x^2*y+8x*y^2+8y^3}}} Distribute



{{{x^3+6x^2*y+12xy^2+8y^3}}} Combine like terms.



So {{{(x+2y)^3=x^3+6x^2y+12xy^2+8y^3}}}