# Circular functions
+Period of $a\sin(bx)$ is ${2\pi} \over b$
+
+Period of $a\tan(nx)$ is $\pi \over n$
+Asymptotes at $x={2k+1)\pi \over 2n} \> \vert \> k \in \mathbb{Z}$
+
## Reciprocal functions
### Cosecant
+
+
$$\operatorname{cosec} \theta = {1 \over \sin \theta} \> \vert \> \sin \theta \ne 0$$
- **Domain** $= \mathbb{R} \setminus {n\pi : n \in \mathbb{Z}}$
### Secant
+!()[graphics/sec.png]
+
$$\operatorname{sec} \theta = {1 \over \cos \theta} \> \vert \> \cos \theta \ne 0$$
- **Domain** $= \mathbb{R} \setminus \{{{(2n + 1) \pi} \over 2 } : n \in \mathbb{Z}\}$
### Cotangent
+!()[graphics/cot.png]
+
$$\operatorname{cot} \theta = {{\cos \theta} \over {\sin \theta}} \> \vert \> \sin \theta \ne 0$$
- **Domain** $= \mathbb{R} \setminus \{n \pi: n \in \mathbb{Z}\}$