[OS X TeX] Using align with "or"

[Eric van der Oord]

Could :

\usepackage{amsmath}
\[
\begin{array}{lclcl}
  u=0&     \text{or}  &   u+4=0  &    \text{or}  &   u-4=0   \\
  u=0&       &   u=-4  &      &   u=4   \\
  \log x=0&       &   \log x=-4  &      &   \log x=4  
\end{array}
\]

do ?

Eric



Le 17 avr. 2011 à 20:55, David Arnold a écrit :

> All,
> 
> I have such a hard time figuring out how to use the align environment (or alternative) to align the solution of u(u+4)(u-4)=0 and the like.
> 
> I want the first line to read:
> 
> u=0     or     u+4=0     or     u-4=0
> 
> And the second line to read, that is, I want the "or's" removed.
> 
> u=0             u=-4                 u=4
> 
> Ensuing lines are:
> 
> \log x=0    \log x=-4           \log x=4
> 
> Etc.
> 
> I can never figure out how many &'s to use and where to put them so that this will work. Any suggestions?
> 
> Thanks.
> 
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