# Questions tagged [equations]

{equations} is about the various environments to typeset displaystyle mathematics, e.g. equation and {align}. For general questions about mathematical typesetting use {math-mode}. Both tags are possible on the same question.

3,945 questions
8answers
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### Why is $…$ preferable to $$…$$?

I've heard that you should use $...$ for displayed equations instead of $$...$$, but why is that? I'd assumed that it's so that you can more easily tell which are starting and which are ending ...
6answers
632k views

### How can I split an equation over two (or more) lines

I am having the following 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)} ...
5answers
390k views

### eqnarray vs align

Motivation I want to include a list of related equations, say, for a proof, in my LaTeX document. As far as I know, I have two good options, eqnarray and align. Question What is the difference ...
2answers
9k views

### Making equations copyable in pdf

I would like to write a .pdf, where my readers could copy the rendered formulae and paste them directly in their TeX documents. And the copied text would automatically be: \int x\sin ax\;\mathrm{d}x ...
5answers
575k views

### How to break a long equation? [duplicate]

I have a long equation but long enough to occupy two lines. I want to break it to improve readability. How can I break it? F = \{F_{x} \in F_{c} : (|S| > |C|) \cap (minPixels &...
4answers
211k views

### Show equation number only once in align environment

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}
5answers
98k views

2answers
11k views

### How do I number equations only if they are referred to in the text?

I have a paper where all equations are numbered, but I want to number equations only if they are actually referred to in the .tex file using \ref{}. How can I make that happen? Alternatively, how can ...
5answers
234k views

### Reducing font size in equation

I wanted to type an equation in LaTeX. But it is too long to fit into one line. It involves big arrays with many columns so I cannot split it. I wanted to reduce the font size so that it can fit in ...
3answers
151k views

### Symbol for Gaussian distribution

What is the symbol for the normal density function in LaTeX?
3answers
348k views

### How to write partial differential equation (Ex. dQ/dt=ds/dt) with real partial derivative signs?

I would like to make a partial differential equation by using the following notation: dQ/dt (without / but with a real numerator and denomenator). Earlier today I got help from this page on how to ...
3answers
26k views

### How to make a standalone document with one equation?

I was surprised to find that standalone package can not compile a document with an equation: \documentclass{standalone} \begin{document} % not working! F(V, T) = E(V) + D(T) \end{...
6answers
35k views

### How to write a perfect equation parameters description?

Equation's symbols or parameters description are shown below, however, the = and the details of parameter are not aligned. I want to make a parameters list for a equation like this, in which symbols,...
4answers
116k views

### How can I change the font size in math equations?

I find that whenever I'm typing some equations into a document, and the equation gets a bit complex (let's say a fraction in a parentheses, squared, inside a square root, inside a fraction), the ...
1answer
222k views

### Left brace including several lines in eqnarray [duplicate]

How is it possible to make a brace and have something like this in a eqnarray block?
2answers
272k views

### How do you center equations?

I can't seem to center equations without causing some weird formatting problem. The following results in the R being dropped: \begin{center} E(R_{i,t})=E(\alpha_i)+E(\beta_{i,F_1 } F_{1,t})+E(\...
4answers
30k views

### How can I get rid of indentation after an equation?

I'm a total newbie to LaTeX and I get very annoyed about this. Every time I write an equation, the text following the equation has some indentation but I don't want it to be there! Look at the ...
4answers
247k views

### Why \\ does not go to new line in equation?

\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}}{}...
2answers
217k views

### Write 'text' **correctly** in equations

Although many have attempted to explain the difference among \mathrm, \textrm, \textnormal and \text (and others?), I found them misleading. See for example the LaTeX's Wiki \mathrm explanation Why ...
3answers
25k views

### Centering \vdots in a system of many equations

I have a system of equations with an arbitrary number of equations (k). I'd like to use \vdots to compactly describe the system, like so: \begin{align*} R(-1) &= \sum_{i=1}^m A(i)R(i-1) \\ R(-...
5answers
322k views

### Align equation left

Here is my split equation: \documentclass{article} \usepackage{amsmath} \begin{document} \begin{split} a_{ijk} =& \frac {Pr(M_{I} =2 \& M_J=1 \& M_K =1 | I=i , J=j , K=...
2answers
38k views

### How to globally change the spacing around equations?

How could I go about setting the 'above' and 'below' vspaces around the equation environment? If the same could be done for the subequations or gather environments, this would be a bonus.
6answers
11k views

### How can I get an underbrace and an overbrace to partially overlap in an equation?

Sometimes I want to describe portions of an equation using \underbrace and \overbrace in such a way that the portions are not completely distinct, for example: /-------\ x = A + B + C + D + E ...
2answers
35k views

### Multi-page equations — problem

I have a very long derivation, that needs to look like: A = B \\ = C \\ = D \\ etc. The derivation spans across many lines. I'm looking for a way to typeset it so that when it reaches the end of ...
2answers
55k views

### add vertical space between equations

I am using the following code to combine two equations with one number in parentheses but the two equations are very close to each other and using '\vspace{} not working How can i add a vertical ...
4answers
112k views

### Aligned equations in LaTeX

I have a long equation in LaTeX, which I need to break up into more lines. I've done this, although its not quite what I was looking for. Here is a MWE showing my problem: \documentclass[10pt]{...
1answer
69k views

### What is the difference between \eqref and \ref?

Is there any difference between \eqref and \ref? I used both of them in my document using the package classicthesis and saw no difference in the result. Is there any specific situation in which I ...
1answer
38k views

### Multiple Alignment in equations

The following equations need to be aligned in two spots. If I use the align* environment then the second column of alignment is pushed to the right edge of the page. I googled this and saw that ...
11answers
20k views

### Embedding LaTeX equations into a webpage

I'd like to include some basic math equations into a webpage. Is there an easy way of either compiling the LaTeX into an image which I can upload, or else of having the browser parse the code?
3answers
7k views

### Which command should I use for displayed equations?

A number of related questions have already been asked about this issue: align vs equation which is preferable to what to do with this hyperref note on amsmath and even eqnarray vs align But I'm ...
1answer
27k views

### Is there a standard way to refer to a range of equations?

I have occasionally wanted to refer to a range of equations in my document. So far, I've been using Equations~\eqref{firstEquation}~--~\eqref{lastEquation}, which produces something like "Equations (...
1answer
12k views

### Breaking equations with breqn

I am new to using the breqn package. It looks good, but I get an odd behaviour when an equation can almost fit in the page but not quite: the alignment gets completely wrong. Is there a way to fix ...
4answers
14k views

### Sharing alignment between equations in two different items

In the following minimal example, I have two equations inside an itemize environment, with an item per equations. Each equation is defined in its own equation environment. \documentclass{article} \...
3answers
54k views

### Adding letters to equation numbers

I want to number use a equation and add a letter to the equation number such as: f(x) =a x and g(x) = b x (3.1.1a,b) That is e.g. using ... \label{eq} \end{...
2answers
15k views

### Aligned equations inside of TikZ node.

How can I create a tree node with an aligned math equations inside? \begin{align} \end{align} doesn't work \begin{minipage}{100} \begin{align} ... \end{align} \end{minipage} Gives a lot of ...
3answers
19k views

### Guidelines for typesetting fractions

I realize that this question is to some extent subjective. However, I suspect that there are some common standards regarding how fractions ought to be typeset in mathematics. The guide Mathematical ...
2answers
44k views

### Linebreak between \left and \right [duplicate]

Possible Duplicate: How to make \left, \right pairs of delimiter work over multiple lines? I would like to type something like this: \begin{split} \left( ba ba ba \\ ...