Answer
$$-\frac{3\sqrt{a^2-3}}{a^2-3}$$
Work Step by Step
Simplifying the expression using the rules of radicals, we find:
$$ \frac{a^2}{\sqrt{a^2-3}}+\frac{\sqrt{a^2-3}\sqrt{a^2-3}}{\sqrt{a^2-3}}\\ \frac{-3}{\sqrt{a^2-3}}\\ -\frac{3\sqrt{a^2-3}}{a^2-3}$$