Cotangent Function is Odd

Theorem
Let $x \in \R$ be a real number.

Let $\cot x$ be the cotangent of $x$.

Then, whenever $\cot x$ is defined:
 * $\cot \left({-x}\right) = -\cot x$

That is, the cotangent function is odd.

Also see

 * Sine Function is Odd
 * Cosine Function is Even
 * Tangent Function is Odd
 * Secant Function is Even
 * Cosecant Function is Odd