| $$ \begin{aligned}2x^2(7x^2-9x+2)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}14x^4-18x^3+4x^2\end{aligned} $$ | |
| ① | Multiply $ \color{blue}{2x^2} $ by $ \left( 7x^2-9x+2\right) $ $$ \color{blue}{2x^2} \cdot \left( 7x^2-9x+2\right) = 14x^4-18x^3+4x^2 $$ |