Answer
$8x^3-12x^2y+6xy^2-y^3$
Work Step by Step
Let's use the concept of cubing the binomial given by $$(x-y)^3=x^3-3x^2y+3xy^2-y^3$$ Hence,
$\begin{align}(2x-y)^3&=(2x)^3-3(2x)^2(y)+3(2x)(y)^2-y^3\\&=8x^3-3y(4x^2)+6xy^2-y^3\\&=8x^3-12x^2y+6xy^2-y^3\end{align}$
