Beamer Question: How to get an over or underbrace slide for previous slide elements in Beamer

[Dave94705]

I want to have an equation displayed through a series of Beamer slides within a frame. Then at the end, I want to put an over or underbrace on that existing displayed equation. Example

slide n ends up displaying the equation $$E = m c^2$$
slide n+1 displays something to the effect:

$$\overbrace{E = m c^2}^{\text{Einstein's Big Equation}}$$

Basically, I don't see how to apply the \overbrace at slide n+1 to what exists on slide n -- it is not a simple addition to an existing TeX element, TeX is applying something to an existing TeX element.

Any suggestions? Thanks, ds

[François Patte]

A construction like this:

\begin{frame}

\only<n>{$$E = m c^2$$}

\only<n+1>{$$\overbrace{E = m c^2}^{\text{Einstein's Big Equation}}$$}

\end{frame}

You will have to adjust the vertical and horizontal spaces according to
the effect you want.




--
François Patte
Université Paris Descartes