Question

Find the product:

(x² − 3x + 7)(2x + 3)

Answer 1

By column method:

$$\begin{gathered} {\mathrm{x}}^2-3\mathrm{x}+7 \\ \underline{\times (2\mathrm{x}+3)} \\ 2{\mathrm{x}}^3-6{\mathrm{x}}^2+14\mathrm{x} \\ \underline{3{\mathrm{x}}^2-9\mathrm{x}+21} \\ \mathrm{Add}:2{\mathrm{x}}^3-3{\mathrm{x}}^2+5\mathrm{x}+21 \\ \therefore ({\mathrm{x}}^2-3\mathrm{x}+7)(2\mathrm{x}+3)=2{\mathrm{x}}^3-3{\mathrm{x}}^2+5\mathrm{x}+21 \end{gathered}$$