Tap the blue circles to see an explanation.
$$ \begin{aligned}\frac{5\sqrt{2}}{2\sqrt{2}-2}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{5\sqrt{2}}{2\sqrt{2}-2}\frac{2\sqrt{2}+2}{2\sqrt{2}+2} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}\frac{20+10\sqrt{2}}{8+4\sqrt{2}-4\sqrt{2}-4} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}\frac{20+10\sqrt{2}}{4}\end{aligned} $$ | |
① | Multiply the numerator and denominator by the conjugate of the denominator . $$\color{blue}{ 2 \sqrt{2} + 2} $$. |
② | Multiply in a numerator. $$ \color{blue}{ 5 \sqrt{2} } \cdot \left( 2 \sqrt{2} + 2\right) = \color{blue}{ 5 \sqrt{2}} \cdot 2 \sqrt{2}+\color{blue}{ 5 \sqrt{2}} \cdot2 = \\ = 20 + 10 \sqrt{2} $$ Simplify denominator. $$ \color{blue}{ \left( 2 \sqrt{2}-2\right) } \cdot \left( 2 \sqrt{2} + 2\right) = \color{blue}{ 2 \sqrt{2}} \cdot 2 \sqrt{2}+\color{blue}{ 2 \sqrt{2}} \cdot2\color{blue}{-2} \cdot 2 \sqrt{2}\color{blue}{-2} \cdot2 = \\ = 8 + 4 \sqrt{2}- 4 \sqrt{2}-4 $$ |
③ | Simplify numerator and denominator |