Semicircle ADB with diameter 6 is rotated 60∘ anticlockwise at the point A to form another semicircle AEC with diameter AC. Find the area of the shaded region.
B makes a 60 out of 360o cicular area of radius 6
60/360 x pi 6^2 add to this the shaded semicirle area then subtract the unshaded semi circle area and you are left with
60/360 x pi x 6^2 units^2