Answer
$= \frac{1}{2}\log x + \frac{1}{2}\log y - 3$
Work Step by Step
$= \log(\frac{\sqrt {xy}}{1000})$
$= \log(\sqrt {xy}) - \log(1000)$
$= \log(xy)^{\frac{1}{2}} - \log10^{3}$
$= \frac{1}{2}\log xy - 3\log10$
$= \frac{1}{2}\log x + \frac{1}{2}\log y - 3$
