Answer:
![\displaystyle A=(1)/(2)\int_\pi^{(7\pi)/(6)}{(cos(\theta)+sin(2\theta))^2}\,d\theta](https://img.qammunity.org/2021/formulas/mathematics/college/gfzyvugc3nlqahvckp7o2v8xrj1ochrxy2.png)
Explanation:
The shaded area is the area of the curve bounded by θ = π and θ = 7π/6.* A differential of area in polar coordinates is ...
dA = (1/2)r^2·dθ
So, the shaded area is ...
![\displaystyle\boxed{A=(1)/(2)\int_\pi^{(7\pi)/(6)}{(cos(\theta)+sin(2\theta))^2}\,d\theta}](https://img.qammunity.org/2021/formulas/mathematics/college/5rb6p2emukg4nxnbo3iewv250t3ry88lf9.png)
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* We found these bounds by trial and error using a graphing calculator to plot portions of the curve.