Answer
$\frac{(9 - 3\sqrt 7)}{2}$
Work Step by Step
$\frac{3}{(3 + \sqrt 7)}$
= $\frac{3\times(3 - \sqrt 7)}{(3 + \sqrt 7)\times(3 - \sqrt 7) }$
= $\frac{(9 - 3\sqrt 7)}{(3^{2} - \sqrt 7^{2}) }$
= $\frac{(9 - 3\sqrt 7)}{(9 - 7)}$
= $\frac{(9 - 3\sqrt 7)}{2}$
