3.5.2 Greatest hits from previous weeks

Greatest hits from previous weeks:

3.5.2.1 How to typeset subscript in usual text mode?

http://tex.stackexchange.com/questions/1013/how-to-typeset-subscript-in-usual-text-mode

It's easy to make subscripts in math mode: $a_i$. 
How do I make a subscript outside math environment, likethis?
 

- asked by Pavel Shved (156 votes), answered by Stefan Kottwitz (103 votes)

3.5.2.2 How do I turn off equation auto numbering

http://tex.stackexchange.com/questions/2597/how-do-i-turn-off-equation-auto-numbering

I have an equation like this: 
\begin{align} 
P(A \cup B) = \sum_{\omega \in A \cup B} P(\omega) = \sum_{\omega \in A} P(\omega) + \sum_{\omega \in B} P(\omega) 
= P(A) + P(B) 
...
 

- asked by user1046 (71 votes), answered by levesque (78 votes)