Solving $f'(x) = f(f(x))$
Does a non-trivial solution exist for $f'(x)=f(f(x))$?
How to reproduce this box in tcolorbox I'm working with tcolorbox, I saw the pdf  and I want to reproduce the little green box in this image:     Can anyone help me please? What software do you use to keep up to date on literature, and if Google Scholar, how do you avoid information overload? Finding an expression for $\tan (a+ b + y)$ which involves only $\tan a, \tan b,$ and $\tan y$. How to find this ?   I'm stuck at $1$ and how to $1$ to change the tangent associated with a,b or c.  I meant this ,everybody.  $\frac{tan(a)+tan(b)+tan(y)−tan(a)tan(b)tan(y)}{1−tan(a)tan(b)−tan(a)tan(y)−tan(b)tan(y)}$ Where to locate "sockets" I am new to this, so sorry if its obvious. I am running a Debian server and installing the likes of UWSGI, NGinx etc on there. The configurations keep talking about pointing to "sockets".  In the build options I seem to be able to specify where the sockets for each program go. By default it looks like most of them go in /tmp (not all of them).  Is this a good place for them to go? I'm trying to keep things as organized as possible but just bunging them in /tmp doesn't seem like the best option. Do you have advantage when multiple sources give advantage and only one gives disadvantage? As I understand it:   if you have Advantage from two different sources, you simply have Advantage (no stacking) if you have advantage from one source, and disadvantage from one source, they cancel out.     So what if you have advantage from two or more sources, and disadvantage from one source?  My assumption is that you simply have advantage, or put another way, you have Advantage on a roll when the # of Advantages > # of Disadvantages (and vice versa).  Is that correct? I have just asked a question on   I read from this meta answer  that suggested     From a desktop support perspective there are certainly cases where a   large(r) number of machines will be affected by something, in which   case it's appropriate for SF. There are then others that are isolated   to a single computer, these tend to be the ones I vote to move to SU.   Since my question is clearly not about a single computer and is external to a single computer, I turned to ServerFault. I thought the question is about how to replicate a network admin strategy on my own (home) network. My question is, however, marked as off-topic, and I did see that homenetwork questions are off-topic. But this is not a single computer issue either.  My question is:  Where should such home/small network questions be asked?  What's the real difference between "professional" networks and the smaller networks that I build for my home or lab with a handful computers?  -- UPDATE --  The question asked here is different from the said duplicate question  as that question is about the difference among computer science and programming SE sites. It has nothing to do with network administration, whether it's large or small networks. None of the two SE sites in question (Server Fault and Super User) is even mentioned in the question or in the 2 cited answers.  -- UPDATE2 --  This question is not a duplicate of , which was cited in the OP and was the cause of this question. That question does not cover the overlapping area of small networks, which could both be for work and for home network. Strange character when using listings package I'm seeing an odd character like a very flat U, where there should be a space, with the listings package. See example below. Does anyone have any idea why this is happening, or how to get rid or work around it?  \documentclass{standalone} \usepackage{underscore} \usepackage{listings} \usepackage[usenames,dvipsnames, rgb, svgnames, x11names]{xcolor} % Text layout \topmargin 0.0cm \oddsidemargin 0.5cm \evensidemargin 0.5cm \textwidth 16cm \textheight 21cm  \lstnewenvironment{cmd}[1][]{%   \lstset{language=sh, backgroundcolor=\color{LightSteelBlue1}, #1}} {}  \begin{document} \begin{cmd}[caption=Configuration file section including filters] [affy6] [...]     [[hapmap]]     phenofiles = "data/Hapmap6.0/Pheno/hapmappheno_909.csv",     genofile = "/data/snppy/Hapmap6.0/Geno/birdseed-v2.calls.txt"     anno_filter = "chromosome = 5"     idlink_filter = "studyid = 'CEU'"     some_other_stuff = "foo = bar" \end{cmd} \end{document} Approximation of measurable function by simple functions I am nearing the end of my PhD and I would quite like to buy a "thank you" gift for my supervisor (although, she's the socially awkward type who I'm sure will be greatly embarrassed to receive one).  I'm just wondering whether a gift is the done thing? And if so, what sort of gift seems appropriate? I suppose a bottle of wine would be a safe choice? Why is it a bad practice to lock the object we are going to change? Why can't I have a non-integral static const member in a class? I noticed C++ will not compile the following:  class No_Good {   static double const d = 1.0; };   However it will happily allow a variation where the double is changed to an int, unsigned, or any integral type:  class Happy_Times {   static unsigned const u = 1; };   My solution was to alter it to read:  class Now_Good {   static double d() { return 1.0; } };   and figure that the compiler will be smart enough to inline where necessary... but it left me curious.  Why would the C++ designer(s) allow me to static const an int or unsigned, but not a double?  Edit: I am using visual studio 7.1 (.net 2003) on Windows XP.  Edit2:  Question has been answered, but for completion, the error I was seeing:  error C2864: 'd' : only const static integral data members can be initialized inside a class or struct What is the difference between image size and image quality? Can I choose which records are copied in a Partial Copy sandbox? We have a partial copy sandbox that we're using for development and testing.  This is really helpful as some of our applications internally store Salesforce id's.  However, there is a limitation with the partial copy as it only brings in 10,000 records per object from the production environment.  Unfortunately some of the id's we internally store are not being brought down into our partial copy which causes errors.  The 10,000 records that it did copy over aren't needed; I realistically only need 1 or 2.  Is there any way I can achieve copying over a specific record from the production environment? How to integrate $\int\sqrt{x^2+1}dx$ I have a skyscraper building but I only want the glass in the texture to be glossy.  How would I accomplish this?    Ok, I have done a test and here are the results.  Here is the original:   here is an adjusted image I have multiple characters linked to a blender file, but i moved the original character files and now blender is sating they're missing.  Is it possible to get blender to find the missing blender files like it finds missing image files so that i can preserve the previously made animation?  On a side note is there a way to also view a list of all the missing files? Get text from pressed button Function always continuous in a Sobolev Space? Hy everybody got a quick question. I know that all function F in a Sobolev Space has a continuous representative called U such as U=F almost everywhere.  Lets take for example: The Sobolev space on ]-1,1[    the function F(x)=0 on x&lt;0 and F(x)=1 x>0  we can't find a continuous representative because it would be on a larger interval let say ]-eps ,eps[ so not in a Sobolev space the function F(x)=x on x&lt;0 and x>0 and F(0)=1 where we could find the representative U=x   My question is: if F isn't continuous is it sure that it isn't an element of a Sobolev Space? It was given was given as a necessary condition in my course.  Thanks for the help. The responsiveness is really bad on a newly installed Ubuntu 14.04 LTS.  Here's the specs of my laptop:  Quadcore Intel i7-4600U CPU @ 2.10GHz 12GB Ram 1TB Samsung EVO SSD   And when gradle is compiling, my entire system slows to a crawl, videos begin stuttering, browser scrolling lags... etc.  The same goes when a page refresh occurs in another window in Chrome, and while it refreshes, the HTML5 video in another tab begins stuttering.  How can I fix this?  Here are some logs:  $ vmstat -a 1 5 -   $ iostat -x 1 5 -   $ top -b - Selection of logical connectives {¬,∨,∧,⇒,⇔} in set theory?