This site is here to facilitate written discourse in mathematics - and, more generally, in technical disciplines. As such, it is often nice to format your questions and responses as nicely as possible - including typeset mathematics, images, and code as appropriate.

Sections and other formatting

Textual entry into discourse is based on Markdown - a lightweight markup language that makes formatting relatively easy. To start this particular section, for example, I simply entered:

## Sections and other formatting

Creating a bulleted list is as easy as indenting with asterisks. To get this:

• First item
• Second item
  • A sub item

Just type this:

* First item
* Second item
  * A sub item

And code like the above is entered by indenting four spaces.

Mathematical typesetting

Beautifully typeset mathematics is created using a system called LaTeX, which is a general technical document preparation system. One of our objectives in this class is to help you learn this fabulous tool. Discourse provides a gentle introduction to it, since you can focus on just little snippets. We're actually using a library called MathJax which is an implementation of LaTeX's typesetting engine in Javascript.

The basic idea is easy to illustrate with an example. Suppose I want to create $f(x)=x^2$.

Note that it looks like nicely typeset mathematics - textbook quality. To get this line, I just type in: $f(x)=x^2$.

The dollar signs delimiters indicate that we want typeset math. That example was inline but we might want the math set aside in display form, particularly if it's longer or more complicated. If I want

$$f(x) = x^2 \implies f(2) = 4,$$

I'd type in

$$f(x) = x^2 \implies f(2) = 4,$$

The only real difference is the double dollar signs, rather than the single.

There is a pretty good MathJax tutorial on Math Stackexchange's Meta site.

Practice

I'm going to practice a little typesetting, if you don't mind.

Inline

Here's $f(x) = x^3-x$.

Display Form

And the same thing set aside:

$$f(x) = x^3 - x.$$