Thực hiện phép tính: a) (x + 3)^3; b) (x-2/5)^3; c) (3.m^2 + n/4)^3

* Hướng dẫn giải

a) ${\mathrm{x}}^3$ + 9${\mathrm{x}}^2$ + 27x + 27.

b) ${\mathrm{x}}^3-\frac{6}{5}{\mathrm{x}}^2+\frac{12}{25}\mathrm{x}-\frac{8}{125}.$ 

c) $27{\mathrm{m}}^6+\frac{27}{4}{\mathrm{m}}^4\mathrm{n}+\frac{9}{16}{\mathrm{m}}^2{\mathrm{n}}^2+\frac{{\mathrm{n}}^3}{64}.$ 

d) $-\frac{8}{27}{\mathrm{u}}^9-2{\mathrm{u}}^6{\mathrm{v}}^2-\frac{9}{2}{\mathrm{u}}^3{\mathrm{v}}^4-\frac{27}{8}{\mathrm{v}}^6.$