| $$ \begin{aligned}6x^3y^4(4x^2-xy+4y^2)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}24x^5y^4-6x^4y^5+24x^3y^6\end{aligned} $$ | |
| ① | Multiply $ \color{blue}{6x^3y^4} $ by $ \left( 4x^2-xy+4y^2\right) $ $$ \color{blue}{6x^3y^4} \cdot \left( 4x^2-xy+4y^2\right) = 24x^5y^4-6x^4y^5+24x^3y^6 $$ |