Let's side of equilateral triangle=a

ans radius of circle=R=1

Radius of the circumscribed circle is R=a/root of 3

1=a/root of 3

a=root of 3=1.732...................................................................(i)

Area of equilateral triangle=A=(root of 3/4)*a^2

A=(1.732/4)*(1.732)^2=1.299

Area of circle=C=(pi/4)*d^2=(3.142/4)*(2)^2=3.142

Area of shaded portion=C-A=3.142-1.299=1.843

**ans is 1.843**