x^3-3x[1/3x-2(1/2x+2)]
=x^3-3x[1/3x-(x+4)]
=x^3-x[x-3(x+4)]
=x^3-x(x-3x-12)
=x^3-x(-2x-12)
=x^3+2x^2+12x【化简结果】
=x(x^2+2x+12)
=x[(x+1)^2+11]
=-2*(1+11)
=-24