# Poster quality math symbols/formulas presentation

I would like to start/end a lecture by displaying a slide where a short symbol or equation is displayed prominently and fills up about half the screen, hopefully to focus the attention of students. For example it could be just $\int f(x)dx$ or just $\sin^2(x)+\cos^2(x)=1$. I like the equation to be framed (circular or rectangular) and use some contrasting background/foreground colors. Whatever brings the equation out of the page and has a gong quality to it would help. Any references to such files will be appreciated.

Edits:

Related:

Alain Mattes package of ornamental design used here for borders. Metapost is used for traditional tile-style background.

Math equations in the news. Centering an equation on a cropped image is a useful addition.

• Most fonts are scalable, meaning that resolution scales to the available space. Thus, do you mean something like \documentclass{beamer} \usepackage{xcolor,graphicx} \begin{document} \centering \fboxsep=5pt \scalebox{6}{% \colorbox{blue}{\color{white}$\int f(x)dx$}}\bigskip\par \scalebox{2.8}{% \colorbox{blue}{\color{white}$\sin^2(x)+\cos^2(x)=1$}} \end{document} Nov 2 '15 at 18:37
• @StevenB.Segletes that did not compile, I got an error message, Runaway argument? {\par \end \par \par ! File ended while scanning use of \Gscale@box. <inserted text> \par Nov 2 '15 at 18:57
• It is tough to copy and paste a multi-line code onto a continuous stream comment. But perhaps if you delete the % signs, it should at least compile. (the spaces in the code generally denote a new line) Nov 2 '15 at 18:58
• @StevenB.Segletes yes you are right it works. Thanks Nov 2 '15 at 19:01
• The suggestion to convert the problem to a bonus one came from SE software. At that point I added some observations hoping to make the problem attract some interest. The solution is essentially for introductory class use which others may find useful too. I think SE functions well in this regard. Nov 8 '15 at 3:09

Since no one else has chimed in, I will convert my comment to an answer. As I had said, "most fonts are scalable, meaning that resolution scales to the available space."

The MWE below is a whole beamer slide, and can be seen to retain good resolution to very large font size.

\documentclass{beamer}
\usepackage{xcolor,graphicx}
\begin{document}
\begin{frame}
\centering \fboxsep=5pt
\scalebox{6}{\colorbox{blue}{\color{white}$\int f(x)dx$}}\bigskip\par
\scalebox{2.8}{\colorbox{blue}{\color{white}$\sin^2(x)+\cos^2(x)=1$}}
\end{frame}
\end{document}


Here is an alternative that does four (or five) things:

1. It makes the large equations in a roman, not sans serif, font, by renewing the \mathfamilydefault and

2. It set the integral in \displaystyle.

3. It uses an \fbox rather than \colorbox on the top equation (\fboxsep and \fboxrule are pertinent to the frame offset and thickness), and

4. It provides different color for frame vs. equation.

5. In frame 2, it allows specification of the equation height, rather than a scale factor.

Here is the MWE.

\documentclass{beamer}
\usepackage{xcolor,graphicx,scalerel}
\renewcommand\mathfamilydefault{\rmdefault}
\fboxsep=4pt \fboxrule 1pt
\begin{document}
\begin{frame}
\centering
\scalebox{5}{\color{blue!30!red}\fbox{\color{blue}$\displaystyle\int f(x)dx$}}\bigskip\par
\scalebox{2.8}{\colorbox{blue}{\color{white}$\sin^2(x)+\cos^2(x)=1$}}
\end{frame}
\begin{frame}
\centering
\scaleto{\color{blue!30!red}\fbox{\color{blue}$\displaystyle\int f(x)dx$}}{150pt}
150pt high\bigskip\par
\scaleto{\colorbox{blue}{\color{white}$\sin^2(x)+\cos^2(x)=1$}}{50pt} 50 pt
\end{frame}
\end{document}


Here is frame 1 with a scale factor applied

And here is frame 2 with a vertical height defined:

• Some factors that will improve the solution: making the scalebox automatic, having a more elaborate frame, the font choice could have an effect too, for example the parenthesis in the first equation looks oddly large to me. Nov 7 '15 at 13:57
• For a more semantic alternative, you might try the empheq package for emphasizing equations. Nov 10 '15 at 14:56

Here is my shot: now with lecturer and without metapost, beamer or pgf/tikz. This code should also work with Plain and ConTeXt mkii.

\documentclass{article}
\usepackage{lecturer,concmath}

\begin{document}
%
% Original Author: Paul Isambert.
% Date: July 2010.

\setparameter job:
fullscreen = true
%  font       = \mainfont %define elsewhere

\setparameter slide:
width = 4cm
height= 3cm
top          = 0cm
bottom       = 1cm
left         = 1.2cm
right        = .3cm
topskip      = 0pt
background   = black % For the lines between squares.
foreground   = white
vpos         = center
hpos         = ff

\setarea{area1 area2 matharea}
width = .9cm

\setarea{area1 area2}
height     = .95cm
background = white

\setarea{area2}
vshift     = 1.05cm

\setarea{matharea footnotearea}
height       = .9cm
vshift*      = 0pt
topskip      = .1cm
baselineskip = .333cm
vpos         = center

\setarea{matharea}
background = red
foreground = white
hpos       = rr

% Below the slide's text.
\setarea{mainarea}
hshift     = 1cm
hshift*    = 0pt
height     = 2cm
background = blue

\setarea{footnotearea}
hshift       = 1cm
hshift*      = 1cm
left right   = .3cm
background   = white
%  font         = \footnotefont %define elsewhere
hpos         = ff

\setarea{area6 area7}
width   = .9cm
hshift* = 0pt
height  = .4cm

\setarea{area6}
vshift     = 2.1cm
background = white

\setarea{area7}
vshift*    = 0pt
background = yellow

\slide[A neat showoff]

$$\sum_{k=1}^{n} (2k-1)=n^2$$

\endslide

\end{document}


This strikes me as a good place to use 'blocks' in beamer (I assume you're using beamer).

\documentclass{beamer}
\usetheme{Copenhagen}

\begin{document}

\begin{frame}

\begin{block}{Food for Thought}
\Huge
\begin{align*}
x^2 + y^2 = 1
\end{align*}
\end{block}

\end{frame}

\end{document}


https://www.sharelatex.com/blog/2013/08/16/beamer-series-pt3.html

• The braces around \Huge are not necessary, because the block environment is already a scope. Nov 9 '15 at 23:52
• @egreg, thanks for the tip -- I've edited my answer. Nov 10 '15 at 14:48