This is a test.

So:

• Hello
• Yes

Good!

$$\mathcal{L}=\underset{x\to 0}{\lim }\frac{\sin x}{x}=1.$$

And

$$\left|\begin{array}{ccc}1& 0& 0\\ 0& 1& 0\\ 0& 0& 1\end{array}\right|=1$$

as well.