Tap the blue circles to see an explanation.
$$ \begin{aligned}\frac{\sqrt{3}}{\sqrt{7}+\sqrt{2}}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{\sqrt{3}}{\sqrt{7}+\sqrt{2}}\frac{\sqrt{7}-\sqrt{2}}{\sqrt{7}-\sqrt{2}} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}\frac{\sqrt{21}-\sqrt{6}}{7-\sqrt{14}+\sqrt{14}-2} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}\frac{\sqrt{21}-\sqrt{6}}{5}\end{aligned} $$ | |
① | Multiply the numerator and denominator by the conjugate of the denominator . $$\color{blue}{ \sqrt{7}- \sqrt{2}} $$. |
② | Multiply in a numerator. $$ \color{blue}{ \sqrt{3} } \cdot \left( \sqrt{7}- \sqrt{2}\right) = \color{blue}{ \sqrt{3}} \cdot \sqrt{7}+\color{blue}{ \sqrt{3}} \cdot- \sqrt{2} = \\ = \sqrt{21}- \sqrt{6} $$ Simplify denominator. $$ \color{blue}{ \left( \sqrt{7} + \sqrt{2}\right) } \cdot \left( \sqrt{7}- \sqrt{2}\right) = \color{blue}{ \sqrt{7}} \cdot \sqrt{7}+\color{blue}{ \sqrt{7}} \cdot- \sqrt{2}+\color{blue}{ \sqrt{2}} \cdot \sqrt{7}+\color{blue}{ \sqrt{2}} \cdot- \sqrt{2} = \\ = 7- \sqrt{14} + \sqrt{14}-2 $$ |
③ | Simplify numerator and denominator |