Question

3(2x-y)^3+3(2x+y)(4x^2-2xy+y^2)-6xy(3y-6x)

Answer 1

$3(2x-y)^3+3(2x+y)(4x^2-2xy+y^2)-6xy(3y-6x)=\ 3(8x^3-12x^2y+6xy^2-y^3)+\3(8x^3-4x^2y+2xy^2+4x^2y-2xy^2+y^3)-\3(6xy^2+12x^2y)=\ 3(16x^3)=48x^3$