# Tangent of Zero

## Theorem

$\tan 0 = 0$

where $\tan$ denotes tangent.

## Proof

 $\displaystyle \tan 0$ $=$ $\displaystyle \frac {\sin 0} {\cos 0}$ Tangent is Sine divided by Cosine $\displaystyle$ $=$ $\displaystyle \frac 0 1$ Sine of Zero is Zero and Cosine of Zero is One $\displaystyle$ $=$ $\displaystyle 0$

$\blacksquare$