Answer
$$\frac{5+\sqrt{2}}{4+\sqrt{8}}=\frac{8-3\sqrt{2}}{4}$$
Explanation
Tap the blue circles to see an explanation.
| $$ \begin{aligned}\frac{5+\sqrt{2}}{4+\sqrt{8}}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{5+\sqrt{2}}{4+\sqrt{8}}\frac{4-\sqrt{8}}{4-\sqrt{8}} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}\frac{20-10\sqrt{2}+4\sqrt{2}-4}{16-8\sqrt{2}+8\sqrt{2}-8} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}\frac{16-6\sqrt{2}}{8} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle4}{\textcircled {4}} } }}}\frac{8-3\sqrt{2}}{4}\end{aligned} $$ | |
| ① | Multiply the numerator and denominator by the conjugate of the denominator . $$\color{blue}{ 4- \sqrt{8}} $$. |
| ② | Multiply in a numerator. $$ \color{blue}{ \left( 5 + \sqrt{2}\right) } \cdot \left( 4- \sqrt{8}\right) = \color{blue}{5} \cdot4+\color{blue}{5} \cdot- \sqrt{8}+\color{blue}{ \sqrt{2}} \cdot4+\color{blue}{ \sqrt{2}} \cdot- \sqrt{8} = \\ = 20- 10 \sqrt{2} + 4 \sqrt{2}-4 $$ Simplify denominator. $$ \color{blue}{ \left( 4 + \sqrt{8}\right) } \cdot \left( 4- \sqrt{8}\right) = \color{blue}{4} \cdot4+\color{blue}{4} \cdot- \sqrt{8}+\color{blue}{ \sqrt{8}} \cdot4+\color{blue}{ \sqrt{8}} \cdot- \sqrt{8} = \\ = 16- 8 \sqrt{2} + 8 \sqrt{2}-8 $$ |
| ③ | Simplify numerator and denominator |
| ④ | Divide both numerator and denominator by 2. |
This page was created using
Rationalize Denominator Calculator