View source for Help:Equations

==General rules==
* '''&lt;math&gt;...&lt;/math&gt;''' - formula must be in MATH tag.
* '''\frac{first line}{second line}''' - fraction
<math>\frac{first line}{second line}</math>
* '''\cdot''' - multiplication sign (don't use x, unless you multiply arrays)
<math>a \cdot b</math>
* '''\sqrt{}''' - square root
<math>\sqrt{2}</math>
* '''&amp;sigma;''' - greek letters
<math>&sigma;</math>
* '''\sum_{k=1}^N k^2''' - sum, power
<math>\displaystyle \sum_{k=1}^N k^2</math>

Full rules are available on Mediawiki site: [http://meta.wikimedia.org/wiki/Help:Formula Formula].

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