Find the integral. (hint: draw pictures)
calculate the missing area
describes half of a circle sitting on top of the x-axis. The area we want is the area inside the purple 2-by-1 rectangle, but not inside the half-circle:
The rectangle has area 2 and the half-circle has area , so
For a sanity check, this is approximately 0.429, which is positive, as would be expected when finding the integral of a non-negative function.