$$ \begin{aligned}\frac{10n^3+50n^3}{n^3+12n+35}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{60n^3}{n^3+12n+35}\end{aligned} $$ | |
① | $$ \color{blue}{10n^3} + \color{blue}{50n^3} = \color{blue}{60n^3} $$ |