CAT 2018 Geometry & Mensuration — Previous Year Question

Two circles with radius $2R$ and $\sqrt{2}R$ intersect each other at points $A$ and $B$. The centers of both the circles are on the same side of $AB$. $O$ is the centre of the bigger circle and $\angle AOB$ is $60^\circ$. Find the area of the common region between the two circles.