Answer
(a) $\frac{2\pi}{3}$
$-\frac{4\pi}{3}$
(b) $\frac{98\pi}{45}$
$-\frac{82\pi}{45}$
Work Step by Step
(a) $\frac{8\pi}{3}-2\pi=\frac{8\pi}{3}-\frac{6\pi}{3}=\frac{2\pi}{3}$
$\frac{2\pi}{3}-2\pi=\frac{8\pi}{3}-2(2\pi)=\frac{8\pi}{3}-\frac{12\pi}{3}=-\frac{4\pi}{3}$
(b) $\frac{8\pi}{45}+2\pi=\frac{8\pi}{45}+\frac{90\pi}{45}=\frac{98\pi}{45}$
$\frac{8\pi}{45}-2\pi=\frac{8\pi}{45}-\frac{90\pi}{45}=-\frac{82\pi}{45}$
