In a display-equation environment I can't get the cases environment to
work properly, unless I just use the first column.
I get the error:
Misplaced alignment tab character &.
s &
s\end{cases}$
I can't figure out why you would want to use a tab mark
here. If you just want an ampersand, the remedy is
simple: Just type `I\&' now. But if some right brace
up above has ended a previous alignment prematurely,
you're probably due for more error messages, and you
might try typing `S' now just to see what is salvageable.
Furthermore, if I just use the left column, then it is displayed all on
one line.
Has someone got this to do anything useful?
Sam
