Question

Find the product:

(x² − y²)(x + 2y)

Answer 1

$$\begin{gathered} ({\mathrm{x}}^2-{\mathrm{y}}^2)(\mathrm{x}+2\mathrm{y}) \\ ={\mathrm{x}}^2\times (\mathrm{x}+2\mathrm{y})-{\mathrm{y}}^2\times (\mathrm{x}+2\mathrm{y}) \\ =({\mathrm{x}}^2\times \mathrm{x}+{\mathrm{x}}^2\times 2\mathrm{y})-({\mathrm{y}}^2\times \mathrm{x}+{\mathrm{y}}^2\times 2\mathrm{y}) \\ ={\mathrm{x}}^3+2{\mathrm{x}}^2\mathrm{y}-{\mathrm{xy}}^2-2{\mathrm{y}}^3 \end{gathered}$$