8.67.2 Greatest hits from previous weeks

8.67.2.1 How can I split an equation over two (or more) lines
8.67.2.2 Using \footnote in a figure's \caption
8.67.2.3 How to write two dot above a letter?
8.67.2.4 Why does \\ not return a new line in an equation?
8.67.2.5 Show equation number only once in align environment
8.67.2.6 The \bar and \overline commands
8.67.2.7 Putting two images beside each other
8.67.2.1 How can I split an equation over two (or more) lines

https://tex.stackexchange.com/landing/r/digest?cta=question&id=3782

I am having the following equation: 
\begin{equation} 
Q(\lambda,\hat{\lambda}) = -\frac{1}{2} P(O \mid \lambda ) \sum_s \sum_m \sum_t \gamma_m^{(s)} (t) \left( n \log(2 \pi ) + \log \left| C_m^{(s)} ... 
[math-mode] [equations] [line-breaking] [breqn]
 
asked by Peter Smit https://tex.stackexchange.com/landing/r/digest?cta=user&id=459 Score of 326
answered by Will Robertson https://tex.stackexchange.com/landing/r/digest?cta=user&id=179 Score of 209
8.67.2.2 Using \footnote in a figure's \caption

https://tex.stackexchange.com/landing/r/digest?cta=question&id=10181

Maybe this is an easy one, but I struggled with this now too long :) 
I want to have a footnote in a caption of a figure, see the example. 
\begin{figure}[!ht] 
\caption{a figure caption\footnote{... 
[floats] [footnotes] [captions]
 
asked by Matten https://tex.stackexchange.com/landing/r/digest?cta=user&id=1125 Score of 303
answered by Dee https://tex.stackexchange.com/landing/r/digest?cta=user&id=16059 Score of 224
8.67.2.3 How to write two dot above a letter?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=152951

the two dots above a letter represents two derivative of varible t. 
My method: 
\documentclass[UTF8]{ctexart} 
\usepackage{amsmath} 
\usepackage{amssymb} 
\usepackage{graphicx} 
\usepackage{epstopdf} 
\... 
[math-mode] [accents]
 
asked by mma https://tex.stackexchange.com/landing/r/digest?cta=user&id=43727 Score of 131
answered by Cain https://tex.stackexchange.com/landing/r/digest?cta=user&id=28428 Score of 184
8.67.2.4 Why does \\ not return a new line in an equation?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=194236

\begin{equation*}\label{eq:pareto mle2} 
A_0 = \frac{1}{(\alpha+t_x)^{r+s+x}}{}_2F_1\left(r+s+x,x+1;r+s+x+1;\frac{\alpha-\beta}{\alpha + t_x} \right ) "\\\" <br> 
- \frac{1}{(\alpha+T)^{r+s+x}}{}... 
[equations] [line-breaking]
 
asked by user3714137 https://tex.stackexchange.com/landing/r/digest?cta=user&id=60029 Score of 108
answered by Mico https://tex.stackexchange.com/landing/r/digest?cta=user&id=5001 Score of 51
8.67.2.5 Show equation number only once in align environment

https://tex.stackexchange.com/landing/r/digest?cta=question&id=17528

I want the equation number to be shown only at the last line, or better, somewhere in the middle of all. So instead of (1), (2), ... only (1). 
I use \begin{align} ... \end{align} 
[equations] [align]
 
asked by Theta30 https://tex.stackexchange.com/landing/r/digest?cta=user&id=5350 Score of 248
answered by Gonzalo Medina https://tex.stackexchange.com/landing/r/digest?cta=user&id=3954 Score of 233
8.67.2.6 The \bar and \overline commands

https://tex.stackexchange.com/landing/r/digest?cta=question&id=22100

I want to represent, say, the closure of a set or the extended reals, e.g., $\bar{\mathbb{R}}$ but unfortunately this creates a bar that is much too small (horizontally) and can barely be seen. On the ... 
[stacking-symbols]
 
asked by 3Sphere https://tex.stackexchange.com/landing/r/digest?cta=user&id=6487 Score of 174
answered by Danie Els https://tex.stackexchange.com/landing/r/digest?cta=user&id=1683 Score of 96
8.67.2.7 Putting two images beside each other

https://tex.stackexchange.com/landing/r/digest?cta=question&id=148438

If I want to put two images beside each other, what should I do? I have inserted a figure. But, rather than having the next figure on a new line, I want it to be beside the already inserted figure. ... 
[graphics] [floats] [positioning]
                                                                                  

                                                                                  
 
asked by Simplicity https://tex.stackexchange.com/landing/r/digest?cta=user&id=28871 Score of 79
answered by Masroor https://tex.stackexchange.com/landing/r/digest?cta=user&id=14103 Score of 174