Greek symbols are very important in equations: \phi, \pi, \Xi. eLyXer offers a complete set in both upper case: \Gamma\ldots\Omega and lower case: \alpha\ldots\omega. Also the AMS italicized upper case: \varGamma\ldots\varOmega.
eLyXer supports the whole set of math symbols in John D. Cook's list: \exists\partial\nabla\geq. It can also render a few more: \propto\times. You also get all symbols from Markus Kuhn's list: \bigodot\amalg.
There are other symbols like arrows: \leftarrow\rightarrow, or geometrical shapes: \circ, \square. eLyXer offers limited support for them. You might also want to use financial symbols in formulae: \yen\euro\$.
Equations look good when items are properly separated. The main separation is the Medium Mathematical Space: x=3.
Note: if you are viewing the non-Unicode version math.html of this page then you are in fact seeing midspaces, which are very similar but not exactly the same: \frac{4}{18}\mathrm{em} for medium mathematical spaces versus \frac{1}{2}\mathrm{en}, where 1\mathrm{em}=2\mathrm{en}. Try out the Unicode version math-unicode.html — and viceversa. You can check out what version this page is in the page title.
The command \raisebox is useful to, surprisingly, raise a little box,
By default, letters denote variables and are taken from the \mathnormal font, which is italic, \alpha x+\alpha y=\alpha(x+y), with the exception of upright capital Greek letters, G\ne\Gamma.
Function names should be upright: \sin(2\pi),\log(x),\tan\delta.
Mathematical fonts used in equations include \mathrm{Roman} (\mathrm), \mathsf{Sans\: Serif} (\mathsf), \mathtt{Typewriter} (\mathtt), \mathbf{Bold} (\mathbf), \mathscr{SCRIPT} (\mathscr), \mathcal{CALLIGRAPHIC} (\mathcal), \mathbb{BLACKBOARD\: BOLD} (\mathbb), and \mathfrak{Fraktur} (\mathfrak). For the latter, some single characters are translated to their Unicode equivalents: \mathscr{F}, \mathbb{F}, \mathfrak{F}.
Regular text in a formula can be achieved via text font commands like \textrm: 5\:\textrm{to}\:10, via boxes like \mbox (prevents line breaks): 6\mbox{ is more than }5, or the AMSmath \text macro (scales like math symbols) \text{base}_{\text{sub}}^{\text{super}}. The content of an mbox is processed in LaTeX text mode. This allows text font commands, e.g. a switch to sans-serif-bold-italic, or the phonetic alphabet: \mbox{\textbf{\textsf{\textbf{\textit{sfbfit}}}}, \textipa{tipa}}.
Units should be written upright, either with \mathrm or with macros from the units package, e.g. as simple unit, \unit{km}, with magnitude, \unit[57]{km}, with fractional unit, \unitfrac[200]{km}{h}, or with a fraction before the units, \unit[\nicefrac{3}{2}]{km}, \unit[\frac{7}{16}]{s}.
\lim_{x\rightarrow\infty}f(x) should appear as x\rightarrow\infty in italics, and «lim» in plain style. In display mode, a limit must appear below the main symbol:
where the sum’s limits should appear below (i=1) and above (\infty) the \sum. The placement of the integral limits depends on the document class: LaTeX standard classes place them right to the \int. Limits are shown to the right in inline formulae: \sum_{i=1}^{\infty}x and \intop_{i=1}^{\infty}x.
The placing of limits can be configured with the \limits and \nolimits macros:
In this section we will explore oducesatisfaction (or were not bugged enough to write about it). Thanks to those who have criticized the tool for making eLyXer improve every day, if only to prove you wrong. And finally thanks to all those who have helped and yet I am now forgetting about them, for not hating me for it.