(i)[4]
Express the perimeter of the shaded region in terms of $r$, $\theta$, and $\pi$.
(ii)[3]
Given $r = 5$ cm and $\theta = 0.6$, determine the area of the shaded region.
Mathematics 9709 · AS & A Level · Circular measure
Circular measure — practice question
In the diagram, $AOB$ makes a quarter circle with centre $O$ and radius $r$. Point $C$ is on arc $AB$, and point $D$ is on $OB$. The line $CD$ runs parallel to $AO$, and angle $AOC = \theta$ radians.