I would like some help with this indefinite integral problem.

$\displaystyle \int\frac{6dx}{\sqrt{4-(x+1)^2}}$

I know that the answer is going to have arcsin in it, but I don't know what to make u. I've tried $\displaystyle (x+1)$, but I don't know how to get rid of the 4. Any assistance on this problem would be greatly appreciated. Thank you.