I have problems for HW that state find the absolute maximum and minimum values of each function on the given interval. Then graph the function. Identify the points on the graph where the absolute extrema occur and include their coordinates.

The first one is

g(x)= sq root(4-x^2) -2 is less than or equal to x is less than or equal to 1

The first thing I did was find the derivative which was -x / sq root (4-x^2)

I am not sure what to do from here. How do I find the absolute max and min?