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First find the intersections between the two curves, they are the limits of integration. They can be found readily as x=±2.
Next, we check that the curves do not cross the axis y=-1 between the limits of integration. Otherwise the limits of integration must change.
Now use the washer method to calculate the area, since the "outer" radius R is based on the upper curve, and the inner radius r is on the lower curve.
The integration formula is then
Area = π∫(R(x)^2-r(x)^2)dx