# Revealing LaTeX symbols as if I'm drawing them by hand

I will be creating a video that explains some simple mathematics concepts to high school students. I am fairly confident with LaTeX so intended to use it to typeset any mathematics I was talking about and show that in the video (instead of using a blackboard or something in the background).

Ideally, instead of just displaying an entire formula on the screen I want my video to slowly trace out the LaTeX symbols as I talk, just as you would expect if you were to watch someone physically write the formula down in front of you (for example, the integral sign starts to display from top to bottom, then a little 1 gets drawn from top to bottom at the bottom of the integral sign, then a little 2 gets drawn from top to bottom at the top of the integral sign, and so on)

Does something like this exist?

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Is this the kind of thing you want? It doesn't trace out the symbols though...

It occurred to me that perhaps the beamer documentclass would be appropriate, with its wonderful \pause command. Sadly, according to the documentation, you can not use \pause inside the align environment (and friends)

This command does not work inside amsmath environments like align, since these do really wicked things.

The above 'animation' is actually nothing more than a .gif image. I produced it using the very simple beamer document below, and followed the instructions in

Converting beamer slides to animated images

One thing to note though, is that when using the \pause command you have to introduce otherwise unnecessary grouping {}

\documentclass{beamer}

\begin{document}

\begin{frame}
${\int_{\pause 1}}^{\pause2}\pause x^2 \mathrm{d}x \pause = {\left.\frac{x^3}{3}\pause\right|}_1^{\pause2}$
\end{frame}

\end{document}

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