Add MathJax rendering to chat on all MathJax sites In StackExchange sites that support MathJax the inline markup is rendered in comments but not chat rooms -- at least I noticed this is the case on .  This is awkward, particularly for comment discussions that are moved to chat.
Any chance of MathJax in chat? It would be really nice to be able to use MathJaX (math formulas) in chat.  Not specially for formulae, but for things like $V_{CC}$ in electronics chat would be very useful.
Where does "pay through the nose" originate? Let $R$ a ring, and let $$\displaystyle R[[x]]=\left\{\sum_{k=0}^{\infty}a_k x^k\;\middle\vert\; a_k\in R\right\}$$ with addition and multiplication as defined for polynomials.  We have that $R[[x]]$ is a ring containing $R[x]$ as a subring.  How to prove that if $a_0\in R$ is a unit, then  $\displaystyle\sum_{k=0}^{\infty}a_k x^k$ is a unit in $R[[x]]$? How to prove the function is a constant Let $f\in C[0,1]$ be such  that $\forall \phi\in C[0,1]$ with $\int_0^1\phi \, dx=0$,we have $\int_0^1f\phi \, dx=0$.  Then $f$ is constant.  May be someone can help me proof this problem. Thanks! Books automatically deletes my books when offline, and when there is enough space on device For which positive integer values of $n$ does $a|mn-b?$ I am taking a number theory class, and I was not able to solve this homework problem.   Let $a,$ $b,$ and $m$ be constant positive integers. For which positive integer values of $n$ does $a|mn-b?$   I tried this out for a couple of values, and the values of $n$ satisfying this expression seem to occur in a cycle.  (For example, let $m=2019,$ $a=20,$ $b=19.$ The values of $n$ that work are $1,21,41,61,....$) However, I am not able to show that this always happens. I'd like to be able to introspect a C++ class for its name, contents (i.e. members and their types) etc. I'm talking native C++ here, not managed C++, which has reflection. I realise C++ supplies some limited information using RTTI. Which additional libraries (or other techniques) could supply this information? What does an unprocessed RAW file look like? Biblatex: submitting to a journal Suppose that I moved from BibTeX to biblatex. With BibTeX I just copied the content of .bbl file into final version of my paper before submitting it to a journal. What should I do at same stage having .bbl file produced by biblatex? It is of quite different format. Calculation of limit without stirling approximation $\lim n^n/(e^nn!)=0$ using Stirling approximation it is obvious. But can we do it without using Stirling approximation.  Now series with terms $x^n n^n/n!$ has ROC $1/e$. What we can say about behaviour of power series at endpoints? I know references are syntactic sugar, so code is easier to read and write. But what is the difference between a pointer variable and a reference variable? 35km commute possible? Currently, on every other day I commute to work which is a distance of 18km each way. I enjoy this ride but next year I may be moving to a place which will be about 35km from work. Questions:  1) Would it still be reasonable to commute this kind of distance each way once I have moved?  2) Google maps estimates that this distance would take 2 hours to complete. Would it be possible (depending on the bike and fitness) to do this distance in about an hour? Should I have more than one brokerage account? I have my brokerage business with one particular well-known US brokerage house. I find being able to access my retirement accounts and personal investment accounts through the one interface useful.  However, I was talking with a friend of mine and she said she never puts more than about $50k into any particular brokerage account.  Managing three or four such accounts seems like too much overhead for me. I'd prefer to spend my "investment time" reading up on my investments and researching new ones.  One reason to have more than one brokerage account with different houses is the issue of  insurance:     Within limits, SIPC expedites the return of missing customer property by protecting each customer up to $500,000 for securities and cash (including a $250,000 limit for cash only).   What other reasons could I have to use more than one brokerage account? Adding a Method to an Existing Object Instance I've read that it is possible to add a method to an existing object (i.e., not in the class definition) in Python.   I understand that it's not always good to do so. But how might one do this? Is it possible to create a counter just with wiring? With the new logic gates in the 1.3.1 update, is it possible to create some wiring circuit that counts how many times a trigger was activated? In other words, is it possible to make a circuit that outputs a trigger every two input triggers?  I've done some experimenting but the nature of wires and there being no intrinsic on/off state in Terraria makes it pretty counter-intuitive compared to real world logic circuits. How to create a list template by using CSOM? Closed unit disk homeomorphic to $\mathbb{R}^2$? I've already shown the existence of a homeomorphism between the open unit disc and $\mathbb{R}^2$ and now I'm trying to work out whether the closed unit disc is homeomorphic to $\mathbb{R}^2$ or not. Clearly the only real difference is the fact it includes the points actually on the circle, but because the continuous, invertible, bijective map I defined for the open disc was $\dfrac{x}{1-|x|}$ this clearly is not defined for the points on the line.   Intuitively I'm thinking it's not possible to form a homeomorphism with the closed disk precisely because of these points on the circle but can't really form a decent argument. I was thinking along the lines of showing that the non-open, closed subset $\bar{D}(0,1) \backslash D(0,1)$ (which is just the set of points on the actual circle i.e the boundary/frontier of the closed disk) can't possibly bijectively map to a closed subset of $\mathbb{R}^2$ - which clearly would have to be the case in a homeomorphism.   Any advice would be greatly appreciated. Determining if an arbitrary point lies inside a triangle defined by three points? Is there an algorithm available to determine if a point P lies inside a triangle ABC defined as three points A, B, and C? (The three line segments of the triangle can be determined as well as the centroid if they are needed.)  Grid space is defined as Screen Space, that is, 2D Cartesian with the Y-Axis flipped so "up" is negative y and the origin is the upper left corner. Turn off automatic preview in apple mail Is it possible to turn off automatic preview of attachments when composing an e-mail?  NOTE: Yes I know that I can manually ctr+select the attachment and disable preview, but I want this done automatically In the , the icon color for the various sites seems* incorrect: Whenever I select a main site, the icon is greyed out, and when ever I select the corresponding meta site, the icon is colored. My initial instinct was to think that the colors of the main/meta sites following the &quot;Switch sites:&quot; prompt should be switched. (Actually, it seems like it's just a UI thing. See the edit below.)  *Edit: Actually, the colors are technically not incorrect, since (as Jeremy Banks has pointed out) the icon shows &quot;the other&quot; site of the main/meta pair, and clicking on it is for switching to the respective other site. See the comment thread for some UI improvement ideas. Do we know why there is a speed limit in our universe? This question is about why we have a universal speed limit (the speed of light in vacuum). Is there a more fundamental law that tells us why this is? I'm not asking why the speed limit is equal to $c$ and not something else, but why there is a limit at all. EDIT: Answers like &quot;if it was not..&quot; and answers explaining the consequences of having or not having a speed limit are not--in my opinion-- giving an answer to whether there is a more fundamental way to derive it from a law to explain this limit.