File access permitions and rights
Why does chmod 777 -R / leave the system unusable?
Prove: If $a\mid m$ and $b\mid m$ and $\gcd(a,b)=1$ then $ab\mid m$ Let $G$ be a group and $H$ be a normal subgroup of index $p$ ( a prime ) ; suppose $K$ is a subgroup of $G$ not contained in $H$ , then is it true that $G=HK$ ? ( I know that the fact is true if $p=2$ , but I don't know for the general case . Please help . Thanks in advance ) Winter is Coming It's my understanding that the phrase "Winter is Coming" is the motto of the Stark house, when the story first reaches the wall it's implied that the winter is not a periodic season like it is in our world.  Does the winter refer to a particularly severe season or does a winter only occur every few years? Set Theory: Tree Property Why does the tree property hold for regular cardinals but not singular cardinals? (I.e. There exists a tree of height $\kappa$ with countable levels and no cofinal branch for $\kappa$ a singular cardinal) There have been a number of cases where I would like to thank someone for providing me with a thorough response and give them feedback beyond the vote up. Often I wish people would tell me why they voted me up. Not that the thank you part is necessary but it sets it apart from the other comments related to answering the question itself.  In this type of situation is a "Thank you" acceptable in a comment?     For more information, see  in the . Proof that the largest eigenvalue of a stochastic matrix is $1$ Get number of unread sms Why are we still using CPUs instead of GPUs? It seems to me that these days lots of calculations are done on the GPU. Obviously graphics are done there, but using CUDA and the like, AI, hashing algorithms (think bitcoins) and others are also done on the GPU. Why can't we just get rid of the CPU and use the GPU on its own? What makes the GPU so much faster than the CPU? Epsilon Delta Proof: How do I use the definitions to prove How to access namespace which is part of different project? What is the symbol on the supply voltage that looks like a shaded-in capacitor? I am looking at  (dual low-voltage power amplifier). On the fourth page, there is a sample circuit; right at the V+ input there is a symbol that looks like a capacitor. However, it looks like it is shaded in. What is that? Looking for a simple proof that groups of order $2p$ are up to isomorphism $\mathbb{Z}_{2p}$ and $D_{p}$ . I'm looking for a simple proof that up to isomorphism every group of order 2p (p prime) is either $\mathbb{Z}_{2p}$ or $D_{p}$ (The Dihedral group of order 2p).  I should note that by simple I mean short and elegant and not necessarily elementary. So feel free to use tools like Sylow Theorems, Cauchy Theorem and similar stuff.  Thanks a lot! I have attached an image as an example below. I want to twist a rectangle. Do I have to convert that rectangle into a curve or into mesh and then twist it with ctrl+T?   Please explain with an example. After restarting my computer when I am presented with the initial login screen (the light gray one with the restart and shut down buttons), I see only two of my three user accounts.  If I log in with one of these accounts, I can see, and log in to, the third (missing) account by either:   Logging off (Apple > Log Out...) to reach the second login screen (the dark gray one with sleep/restart/shut down buttons) Clicking on the fast user switching menu.   How can I restore this account in the initial (light gray) login screen?  I tried repairing disk permissions to no avail.  If I create a new account, it does show up in the list. Ubuntu to Kubuntu switch! I have been running Ubuntu for about a year, now I would like to switch to kubuntu. Is it possible that I can port all the configuration data from the home folder of Ubuntu to kubuntu? (Without causing some serious trouble) If I copy all them contents of the home folder (Including the hidden files and folders) will I be able to get the same application configurations ? I know that copying the Thunderbird folder copies the emails on the newer installation, will it work to other applications? django manytomanyfield .add() method Is it possible to set the GPU fan speed using the default free ati driver?  My card (X1900) was deprecated in the fglrx drivers a while back.  The free drivers seem to work with 3D, Compiz and such, but running graphics intensive programs makes my GPU heat up and produce artifacts, while the GPU fan never seems to increase. (When set to 100% in Windows it makes a massively louder noise.) How many times can American Tourist re-enter UK in same 6 month period? What is the proof that the universal constants ($G$, $\hbar$, $\ldots$) are really constant in time and space? Split string on spaces in Java, except if between quotes (i.e. treat \"hello world\" as one token)