SOLUTION: two concentric circles with centre O and radius r and R respectively. if R=3r, express the area of the shaded part in terms of π and r

Algebra ->  Trigonometry-basics -> SOLUTION: two concentric circles with centre O and radius r and R respectively. if R=3r, express the area of the shaded part in terms of π and r      Log On

I assume that the shaded area is between the circles.


Then its area is   -  =  -  =  -  = .     ANSWER