It always helps to draw a picture.
You can have the second circle be centred anywhere on the first, I've just chosen the point
.
It's important to note that the equations of the circles are
and
.
By subtracting the first equation from the second we find
.
So the equations intersect at
.
Putting the equations as
in terms of
gives:
and
.
Since these are symmetrical about the
axis, we can work out the areas enclosed by the above semicircles, and then double it.
So we can finally say:
You will need to use trigonometric substitution to solve these.
Try
for the first
and
for the second.