Question
Answer
$$(5+4\sqrt{2})\cdot(2+\sqrt{2})=18+13\sqrt{2}$$
Explanation
Tap the blue circles to see an explanation.
| $$ \begin{aligned}(5+4\sqrt{2})\cdot(2+\sqrt{2})& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}10+5\sqrt{2}+8\sqrt{2}+8 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}18+13\sqrt{2}\end{aligned} $$ | |
| ① | $$ \color{blue}{ \left( 5 + 4 \sqrt{2}\right) } \cdot \left( 2 + \sqrt{2}\right) = \color{blue}{5} \cdot2+\color{blue}{5} \cdot \sqrt{2}+\color{blue}{ 4 \sqrt{2}} \cdot2+\color{blue}{ 4 \sqrt{2}} \cdot \sqrt{2} = \\ = 10 + 5 \sqrt{2} + 8 \sqrt{2} + 8 $$ |
| ② | Combine like terms |
This page was created using
Simplify Radical Expression