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Each line must end with a {{cmd|NR}}.
There are several built-in commands for displaying mathematical formulas. For instance
<texcode>
\startcases, \stopcases
\startmathmatrix, \stopmathmatrix
\startalign,\stopalign
</texcode>
Each has its own advantage and can be customized: for a thorough understanding of these commands please
refer to Aditya Mohajan's excellent user's guide
[https://wiki.contextgarden.net/images/archive/b/b4/20100530075041!Mathalign.pdf Using \startalign and friends].
These commands can be found in [[source:core-mat.tex|core-mat.tex]] file, which contains
most of the core ConTeXt math macros.
<context source="yes">
This is an example of aligned equations:
\startformula
\startcases[align={right,left},distance=3pt]
\NC 2x + 3y \NC{} = 10 \NR
\NC 3x + 2y \NC{} = 5, \NR
\stopcases
\stopformula
and this is another one:
\startformula
\startmatrix[align={right,left},distance=3pt,left={\left\{}, right={\right.}]
\NC 2x + 3y \NC{} = 10 \NR
\NC 3x + 2y \NC{} = 5 \NR
\stopmatrix
\stopformula
</context>
In these structures it is important (well, in the above example it is not important and the result is the same, but I have been told that it is necessary in some other situations...) to notice that the sign "=" is preceded by "\NC{}, since
otherwise that sign would be considered as a binary operator and the alignment would be
disturbed (at least this is what I guess…Otared K.).
One of the powerful structures in displaying mathematical formulas is the possibility of defining custom maths alignment.
For instance the following definition
<texcode>
\definemathmatrix[alignedcases]
[align={right,left,left},
distance=3pt,
left={\left\{},
right={\right.},
style=\displaystyle]
</texcode>
creates two new commands,
<texcode>
\startalignedcases, \stopalignedcases:
</texcode>
after which one may use them in a displayed formula as follows:
<texcode>
The following formula is displayed in two lines with an appropriate alignment of the equations:
\startformula
\startalignedcases
\NC -\Delta u + g(u) \NC{} = f \NC \quad\mbox{in } \Omega\NR
\NC {\partial u \over \partial {\bf n} } \NC{} = h(u) \NC \quad\mbox{on } \partial\Omega \NR
\stopalignedcases
\stopformula
</texcode>
<context>
\definemathmatrix[alignedcases]
[align={right,left,left},
distance=3pt,
left={\left\{},
right={\right.},
style=\displaystyle]
The following formula is displayed in two lines with an appropriate alignment of the equations:
\startformula
\startalignedcases
\NC -\Delta u + g(u) \NC{} = f \NC \quad\mbox{in } \Omega\NR
\NC {\partial u \over \partial {\bf n} } \NC{} = h(u) \NC \quad\mbox{on } \partial\Omega \NR
\stopalignedcases
\stopformula
</context>
[[Category:Math]]
= Numbered Cases =
[[Category:Math]]
