I need some help here - I don't get what's going on :)

Step 1:

$\displaystyle

\int \frac{dv}{Cv^2 - g} = \int~dt

$

Step 2:

$\displaystyle \frac{1}{2\sqrt{Cg}}~ln \left ( \frac{v\sqrt{C} - \sqrt{g}}{v\sqrt{C} + \sqrt{g}} \right ) = t + A$

What's happening between the two steps? It would be nice with an extra step or two, as this is very hard for me..