I am interested in doing something like the following.  \documentclass{article}  \usepackage{amsmath}  \newenvironment{customeq}{\begin{equation}\begin{split}}{\end{split}\end{equation}}  \begin{document}  This is an equation. \begin{customeq} x=5 \end{customeq}  \end{document}   However, when I try to do this, I get an error saying that \begin{split} has been ended by \end{customeq}.  Is there a way to get around this issue?
I'm trying to define a new environment that consists of a split environment inside an equation environment. But I'm getting an error. Here's what I'm doing:  \documentclass[a4paper,12pt]{article} \usepackage[brazil]{babel} \usepackage[utf8]{inputenc} \usepackage{amsmath} \newenvironment{example}{\begin{equation}\begin{split}}{\end{split}\end{equation}}  \begin{document} \begin{example}oi\end{example} \end{document}   And the error message I'm getting is:   ERROR: LaTeX Error: \begin{split} on input line 8 ended by \end{example}.   I then tried a few other cases. If I remove the splits and define example to be just equation, it runs fine. If I remove the equations and define example to be just split, I get the exact same error message.  In other words: I only get this error when split is involved. Is there a way to make this work?  EDIT: The reason I'm doing this, is because I want a convenient way to create split-equations. I know it's similar to align. I prefer split-equations because the entire line of equations gets a single number for referencing (it's even placed in the middle line). align, however, will force me to \notag each line, otherwise I get a number for each line in the equation (which tends to get messy when equations are long and numerous). It's not the end of the world, but the split-equation combination is just quicker and easier (if I can manage to define a command for it).  Alternatively, the multline environment is not appropriate either, because it doesn't let you manually align each line (like aligning the equal signs). Instead it only lets you push everything left or right.  EDIT2: I just tried this:  \newenvironment{example}{ \begin{equation}\split}{\endsplit \end{equation}}   and got this error  ERROR: LaTeX Error: \begin{equation} on input line 8 ended by \end{example}.   Which is weird, because removing \split and \endsplit entirely doesn't return any errors (so it's not equation's fault).
How is the minimum of a set of IID random variables distributed? If $X_1, ..., X_n$ are independent identically-distributed random variables, what can be said about the distribution of $\min(X_1, ..., X_n)$ in general? Finding $\int^{\infty}_{0}\frac{\ln^2(x)}{(1-x^2)^2} dx$ Calculate  $$\int^{\infty}_{0}\frac{\ln^2(x)}{(1-x^2)^2}dx$$   I have tried to put $\displaystyle x=\frac{1}{t}$ and $\displaystyle dx=-\frac{1}{t^2}dt$  $$ \int^{\infty}_{0}\frac{t^2\ln^2(t)}{(t^2-1)^2}dt$$  $$\frac{1}{2}\int^{\infty}_{0}t\ln^2(t)\frac{2t}{(t^2-1)^2}dt$$  $$ \frac{1}{2}\bigg[-t\ln^2(t)\frac{1}{t^2-1}+\int^{\infty}_{0}\frac{\ln^2(t)}{t^2-1}+2\int^{\infty}_{0}\frac{\ln(t)}{t^2-1}dt\bigg]$$  How can I solve it? Do any queries exist that require RIGHT JOIN, or can they always be re-written with LEFT JOIN?  And more specifically, how do you re-write this one without the right join (and I guess implicitly without any subqueries or other fanciness):   SELECT * FROM t1 LEFT JOIN t2 ON t1.k2 = t2.k2 RIGHT JOIN t3 ON t3.k3 = t2.k3 How can i render the reflections i see in the Look Dev viewport in Blender 2.8 i'm finding blender 2.8 confusing and i'm relatively new to blender in general anyway. While looking at my model in the Look Dev view port i can see reflections.        However, when i render my scene in eevee (and cycles), the reflections aren't rendered     Is there something i'm doing wrong or an option i haven't enabled? How to get a list of applications installed in Ubuntu dash? I'm trying to write a blog post which includes a code segment inside a &lt;pre&gt; tag. The code segment includes a generic type and uses &lt;&gt; to define that type. This is what the segment looks like:  &lt;pre&gt;     PrimeCalc calc = new PrimeCalc();     Func&lt;int, int&gt; del = calc.GetNextPrime; &lt;/pre&gt;   The resulting HTML removes the &lt;&gt; and ends up like this:  PrimeCalc calc = new PrimeCalc(); Func del = calc.GetNextPrime;   How do I escape the &lt;&gt; so they show up in the HTML? How to approximate the student-t CDF at a point without the hypergeometric function? Is there a way to closely approximate the CDF of a student-t distribution at a point $x$ without involving the hypergeometric function? For example, by using a series expansion, or expressing the CDF in terms of simpler functions?  The t-distribution can   $$t = \frac{X\sqrt{n}}{Y}$$  where $X$ is normally distributed with mean 0 and variance $\sigma^2$; $\frac{Y^2}{\sigma^2}$ has a chi-squared distribution. Maybe this expression can help simplify the t CDF?  I am trying to write an algorithm to compute the student-t CDF for any real number, so using the hypergeometric function will be extremely difficult. I am also trying to avoid integrating the PDF to get the CDF. How can a quasar be 29 billion light-years away from Earth if Big Bang happened only 13.8 billion years ago? I was reading through the Wikipedia article on  and came across the fact that the most distant Quasar is 29 Billion Light years. This is what the  exactly says      The highest redshift quasar known (as of June 2011[update]) is ULAS-J1120+0641, with a redshift of 7.085, which corresponds to a proper distance of approximately 29 billion light-years from Earth.   Now I come to understand that the  singularity is believed to be around 13.8 Billion years ago.  So how is this possible? Does the presence of such a quasar negate the Big Bang Theory?   I'm not a student of Physics and was reading this out of (whimsical) curiosity. Is there something I'm missing here or the "proper distance" mentioned in the fact is a concept that explains this?  Edit: My Bad! Here's how..  A simple google search led me to  which says the farthest quasar found is 12.9 billion LYs and not 29 billion. So in the end we have just proven that wikipedia needs more moderation. Any javascript event occurring when user clicks Stop load button? How to combine various armatures? How do I erase/format a harddisk from a live CD? I need to format a drive containing an old install of Ubuntu 10.04, to install Vista (not my idea!) Vista setup apparently refuses to format non-FAT32 or NTFS partitions. However, I can't seem to format it from my live CD (Ubuntu 11.04) at all; I keep getting "device is busy" errors. What is the simplest way to format this drive? Another word for a troll not on the internet The definition of an internet troll:     In Internet slang, a troll (/ˈtroʊl/, /ˈtrɒl/) is a person who sows   discord on the Internet by starting arguments or upsetting people,   by posting inflammatory,[2] extraneous, or off-topic messages in an   online community (such as a forum, chat room, or blog), either   accidentally[3][4] or with the deliberate intent of provoking readers   into an emotional response[5] or of otherwise disrupting normal   on-topic discussion.[6]      This sense of the word troll and its associated verb trolling are   associated with Internet discourse, but have been used more widely.   Media attention in recent years has equated trolling with online   harassment. For example, mass media has used troll to describe "a   person who defaces Internet tribute sites with the aim of causing   grief to families."[7][8]     What is the equivalent for a person who does this type of thing in real life (non-cyber) troll? Where do I put item tags on items inside a chest or your inventory? I am making a Minecraft Mini Game adventure map, and one of the levels has a /setblock command, I am using the command in a way to spawn an item in a chest (Wooden Button) I need the wooden button to have CanPlaceOn tag so it can be placed on a log. I have tried this command: setblock 294 5 -1251 minecraft:chest 0 replace {Items:[{Count:1,Slot:0,id:minecraft:wooden_button,CanPlaceOn:[log]}]}` How to text-to-speech output using command-line? How to get speech output from entered text by using command-line?  Also facility to change speech rate, pitch, volume etc using simple command. How do I navigate to a samba location I've mounted in Nautilus on the command line? Please note: I am two weeks old in Linux. I have found a lot of answers to this question on the internet, tried many, but all failed one way or another. Therefore I dare to ask once again in the hope that someone here could explain it simply :)  Pre-conditions:  In my institute, we have a Samba server. In Windows, it is accessed by going to \\xyz.220.131.233\ and entering the login abc and the password def.   In Ubuntu, I was able to do exactly the same using Nautilus, pressing Ctrl+L and entering smb://xyz.220.131.233/. It then asks for the login and the password and connects. I can even drag a folder from here to the 'Places' and have a shortcut to the remote location.   So far so good. I've just installed Matlab and want to open this remote location. Trying to cd to smb://xyz.220.131.233/ returns      Cannot CD to smb://xyz.220.131.233 (Name is nonexistent or not a directory).   A Mac user in my group told me I first mount the location, but he didn't know how to do it.   Is it true and how do I do it? Linux - why do the su and sudo binaries need to be set-UID root? I am trying to find the correct reason for the stated question. My understanding is that:   sudo needs to read the /etc/sudoers file which is only readable by root, which is why it needs to be set-UID root su is going to create a new shell with a different real and effective UID, and needs to check the password. To check the password, it needs to read /etc/shadow, which is why it needs to be set-UID root. After checking password, it would need to call setuid() on the forked process, and to use an arbitrary UID argument, its parent process must have root as effective UID, so this also makes another reason.   Are the above reasons correct ? Passive aggressive people will sometimes veil insulting, critical, derogatory or generally aggressive comments with humor. The patina of humor makes the comment seem like a joke, not to be taken seriously, all in good fun, and it safeguards the aggressive person. If someone gets offended, they are being too serious, can't take a joke, and so they cannot voice their upset without seeming to be the one escalating the situation, when in fact it was the aggressor who did that.   This behavior seems to lie on a spectrum. On one side are comments which are simultaneously aggressive and genuinely funny (though of course both, especially the latter, are fairly subjective). On the other side would be lame attempts at the behavior, something like "you are fat!... just joking!" in which nothing in the tone or delivery signals a register of humor. In the middle of the spectrum, I imagine, are aggressive statements genuinely delivered as jokes. Their register signals that they are jokes, but they are aggressive rather than funny. They are aggressive comments masquerading as jokes.      A friend once called this "joking on the square", but I have never heard or seen this phrase. This type of comment is both pervasive and psychologically subtle and in my experience there is often an exact word describing such things. If not a word, is there an astute phrase which cuts to the heart of this? Sorting by multiple fields at same time in QGIS? Is it possible to sort multiple fields at the same time in QGIS?    For example, I'd like to sort a table by state name, and then within each state, sort by county name.    This would be the same as the Advanced Sort option available in ArcMap. Provided we have this truth table where "$p\implies q$" means "if $p$ then $q$":  $$\begin{array}{|c|c|c|} \hline p&amp;q&amp;p\implies q\\ \hline T&amp;T&amp;T\\ T&amp;F&amp;F\\ F&amp;T&amp;T\\ F&amp;F&amp;T\\\hline \end{array}$$  My understanding is that "$p\implies q$" means "when there is $p$, there is q". The second row in the truth table where $p$ is true and $q$ is false would then contradict "$p\implies q$" because there is no $q$ when $p$ is present.  Why then, does the third row of the truth table not contradict "$p\implies q$"? If $q$ is true when $p$ is false, then $p$ is not a condition of $q$.  I have not taken any logic class so please explain it in layman's terms.       Administrative note. You may experience being directed here even though your question was actually about line 4 of the truth table instead. In that case, see the companion question  And even if your original worry was about line 3, it might be useful to skim the other question anyway; many of the answers to either question attempt to explain both lines. What does 'close invalidated' mean Recently I flagged  as a duplicate. A few days later, when I checked it again to see if it was closed, I realized it wasn't.    Searching in Meta brought me to , where a comment suggested checking the timeline. So I checked the  and saw that the close flag was set as invalidated.  Does this mean that it was disputed? When I click on it I see only "This item is no longer reviewable." Do I need more reputation (3000+ ?) to view more detailed information?