Question

Answer 1

\(1,=x^3+27-x^3-54=-27\\ 2,=8x^3+y^3-\left(8x^3-y^3\right)=2y^3\\ 3,=x^3-3x^2+3x-1-x^3-8+3x^2-48=3x-57\\ 4,=x^3-x-\left(x^3+1\right)=-x-1\\ 5,=8x^3-5\left(8x^3+1\right)=-32x^3-5\)

Answer 2

1: Ta có: \(\left(x+3\right)\left(x^2-3x+9\right)-\left(x^3+54\right)\)

\(=x^3+27-x^3-54\)

=-27

2: Ta có: \(\left(2x+y\right)\left(4x^2-2xy+y^2\right)-\left(2x-y\right)\left(4x^2+2xy+y^2\right)\)

\(=8x^3+y^3-8x^3+y^3\)

\(=2y^3\)