Answer
$\displaystyle \frac{5}{\sqrt{15}}$
Work Step by Step
$\displaystyle \sqrt{\frac{5}{3}}=\frac{\sqrt{5}}{\sqrt{3}}$
We are rationalizing the numerator, using
$\sqrt[n]{a^{n}}=(\sqrt[n]{a})^{n}=a \qquad$(for positive a)
and $\sqrt[n]{a}\times\sqrt[n]{b}=\sqrt[n]{ab}$
$=\displaystyle \frac{\sqrt{5}}{\sqrt{3}}\color{red}{ \cdot\frac{\sqrt{5}}{\sqrt{5}} }\qquad$ (rationalize)
$=\displaystyle \frac{5}{\sqrt{15}}$
