Tap the blue circles to see an explanation.
| $$ \begin{aligned}\sqrt{5000}-22\sqrt{125}+3\sqrt{5}(2\sqrt{5}-2)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}50\sqrt{2}-110\sqrt{5}+3\sqrt{5}(2\sqrt{5}-2) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}50\sqrt{2}-110\sqrt{5}+30-6\sqrt{5} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle4}{\textcircled {4}} } }}}\frac{50\sqrt{2}-110\sqrt{5}+30-6\sqrt{5}}{1} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle5}{\textcircled {5}} } }}}50\sqrt{2}-116\sqrt{5}+30\end{aligned} $$ | |
| ① | $$ \sqrt{5000} =
\sqrt{ 50 ^2 \cdot 2 } =
\sqrt{ 50 ^2 } \, \sqrt{ 2 } =
50 \sqrt{ 2 }$$ |
| ② | $$ - 22 \sqrt{125} =
-22 \sqrt{ 5 ^2 \cdot 5 } =
-22 \sqrt{ 5 ^2 } \, \sqrt{ 5 } =
-22 \cdot 5 \sqrt{ 5 } =
-110 \sqrt{ 5 } $$ |
| ③ | $$ \color{blue}{ 3 \sqrt{5} } \cdot \left( 2 \sqrt{5}-2\right) = \color{blue}{ 3 \sqrt{5}} \cdot 2 \sqrt{5}+\color{blue}{ 3 \sqrt{5}} \cdot-2 = \\ = 30- 6 \sqrt{5} $$ |
| ④ | $$ 50\sqrt{2}-110\sqrt{5}+30-6\sqrt{5}
= 50\sqrt{2}-110\sqrt{5} \cdot \color{blue}{\frac{ 1 }{ 1}} + 30-6\sqrt{5} \cdot \color{blue}{\frac{ 1 }{ 1}}
= \frac{50\sqrt{2}-110\sqrt{5}+30-6\sqrt{5}}{1} $$ |
| ⑤ | Remove 1 from denominator. |