Câu hỏi 21Khai triển $(x/3-2)^3$. $\frac{x^3}{27}-8$$\frac{x^3}{27}-2x^2+4x-8$$\frac{x^3}{27}-\frac{2x^2}{3}+2x-8$$\frac{x^3}{27}-\frac{2x^2}{3}+4x-8$$\frac{x^3}{27}-\frac{2x^2}{3}+4x-8$
