Thực hiện phép tính: (1/2x + 3)( 2x^2 - 4x + 6)

* Hướng dẫn giải

$\begin{array}{l}\left(\frac{1}{2}\mathrm{x}+3\right)\left(2{\mathrm{x}}^2-4\mathrm{x}+6\right)\\ =\frac{1}{2}\mathrm{x}.2{\mathrm{x}}^2+3.2{\mathrm{x}}^2-\frac{1}{2}\mathrm{x}.4\mathrm{x}-3.4\mathrm{x}+3.6+\frac{1}{2}\mathrm{x}.6\\ ={\mathrm{x}}^3+6{\mathrm{x}}^2-2{\mathrm{x}}^2-12\mathrm{x}+18+3\mathrm{x}\\ ={\mathrm{x}}^3+4{\mathrm{x}}^2-9\mathrm{x}+18\end{array}$