| $$ \begin{aligned}(-4x^2y^3)^3u^3& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}-64x^6y^9u^3\end{aligned} $$ | |
| ① | $$ \left( -4x^2y^3 \right)^3 = (-4)^3 \left( x^2 \right)^3 \left( y^3 \right)^3 = -64x^6y^9 $$ |