Explanation
The area of a portion of a circle with radius 'r' and angle 'a' (in radians) is:
[tex]A_{\text{portion}}=\frac{1}{2}\cdot r^2\cdot a[/tex]
In this problem r = 3m, a = 60º.
First we have to express the angle in radians:
[tex]a=60º\cdot\frac{\pi}{180º}=\frac{1}{3}\pi[/tex]
The area of the shaded region is:
[tex]\begin{gathered} A=\frac{1}{2}\cdot(3m)^2\cdot\frac{1}{3}\pi \\ A=\frac{1}{2}\cdot9m^2\cdot\frac{1}{3}\pi=\frac{3}{2}\pi \end{gathered}[/tex]
Answer
The area is:
[tex]A=\frac{3}{2}\pi[/tex]
