PS is the diameter of a circle of radius 6 cm. The points Q and R cts the diameter Ps. Semi circles are drawn on PQ and Qs as diameters. Find the area of the shaded region.

Explanation

Area of semicircle`(A_1)=(pir^2)/2=pi/2*6^2`

`=18pi cm^2`

Area of semicircle`(A_2)=(pir_1^2)/2=2pi cm^2`

Area of semicircle`(A_3)=(pir_2^2)/2=pi/2*16`

`=8pi cm^2`

Area of shaded region`=(A_1+A_2+A_3)`

`=(18pi+2pi-8pi)`

`=12pi cm^2`.