| $$ \begin{aligned}\frac{1}{\sqrt{1}+\sqrt{3}+\sqrt{5}+\sqrt{1}\cdot5}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{1}{6+\sqrt{3}+\sqrt{5}}\end{aligned} $$ | |
| ① | Simplify numerator and denominator |