\begin{eqnarray[*]}
var_1 & rel_1 & eq1 \\
var_2 & rel_2 & eq2 \\
....
\end{eqnarray[*]}
The eqnarray environment is typically used to display a sequence of equations
or inequalities; it may also be used to manage spacing for long equations.
The \lefteqn
command is useful in
this environment for splitting long equations over several lines.
It is very much like a three-column
array environment, with position argument rcl
,
i.e., the columns are justified right, center, and left, respectively.
(However, \multicolumn
may not be used.)
Consecutive rows are separated by \\
commands and consecutive items within a
row separated by an &
. Any item may be empty, i.e., no text.
A separate equation number is placed on every
line unless that line has a \nonumber
command.
The optional eqnarray*
form does not generate any equation numbers.
A \label
command anywhere within a
row generates a reference to that row's number.