## Precalculus (6th Edition) Blitzer

$\{ \frac{3\pi}{4},\frac{7\pi}{4} \}$
Step 1. The equation gives two solutions: $cot(x)=0$ and $tan(x)=-1$ Step 2. For $cot(x)=0$, we can find all x-values in $[0,2\pi)$ as $x=\frac{\pi}{2}, \frac{3\pi}{2}$ Step 3. For $tan(x)=-1$, we can find all x-values in $[0,2\pi)$ as $x=\frac{3\pi}{4},\frac{7\pi}{4}$ Step 4. We need to exclude $x=\frac{\pi}{2}, \frac{3\pi}{2}$ since the $tan(x)$ becomes undefined at these values. Step 5. The solutions for the original equation in $[0,2\pi)$ are $\{ \frac{3\pi}{4},\frac{7\pi}{4} \}$