Restore default folder chmod
What if I accidentally run command "chmod -R" on system directories (/, /etc, ...)
Proving $\arg(zw)=\arg(z)+\arg(w)$ This is my attempt I know this is incomplete or may even be wrong.   Let $θ_1 \in \arg(z)$ and $θ_2 \in \arg(w)$. Then, $θ_1+θ_2 \in \arg(z)+\arg(w)$. Also, $θ_1+θ_2 \in \arg(zw)$. Is this sufficient for the proof or correct at all? Hope someone could help me out. Thanks.   EDIT: Just to avoid any confusions I will add how $\arg z$ is defined.   $\arg z=\{\text{Arg}\, z+2\pi k\mid k\text{ is an integer}\}$ Does the Dueling Fighting Style prevent using a shield? The Dueling fighting style doesn't seem to state anything about shields, stating that the character can only wield one weapon while fighting to gain the benefit. Does a shield count as a weapon or otherwise stop the damage bonus from occurring? Correct position of "only" Which is grammatically correct?  I can only do so much in this time.  or  I can do only so much in this time. Select an area in rep graph not working on Chrome The "select an area by dragging across the lower chart" thing is not working on Chrome.  Tested with Chrome 13.0.782.220 m, works with Firefox 6.0.1 and IE 8  Quirk: For some reason, if I open an incognito window, it works. Tried clearing the cache and cookies, still not working. Object created by joining several objects doesn't rotate uniformly consistently Aloha.  I'm experiencing a similar problem I had with a prior posting  with another object I created by joining 3 objects that doesn't rotate uniformly consistently.  I tried clearing and applying rotation of individual objects and joined objects to no avail.  I have  as well as object by itself in blend file if you need to see them  Any ideas?  Thanks. What documentation is needed for a tourist to drive a US citizen's car? Custom first page with fancyhdr I'm using the package fancyhdr to format my footers and headers, with my name in the header and a n of m pages format for the footer. Like so:  \pagestyle{fancy} \fancyhf{} % clear all header and footer fields \fancyhead[C]{Name} \fancyfoot[C]{\footnotesize Page \thepage\ of \pageref{LastPage}}   By default, the fancy page style only affects the pages after the first page. I know I can set the first page to the fancy page style using \thispagestyle, but I only want the first page to use the footer, not the header. Is there a way to create a custom style that just the first page will use? So, the question pretty much says it all. I'm on Snow Leopard, and I do a lot of web development, particularly in Rails 3 which makes heavy use of the console.  I've seen some notable bloggers etc. mention Zsh as their preference over Bash, but I don't know what difference it would make.  Could anyone give me a good comparison of what difference there is and what might make one prefer one option or the other? Every element of a group has order $2$. Why, intuitively, is it abelian? Strange bug with "MessageName[a,b] is not of the form symbol::name ", Debugger & cursor location How do you correctly say large numbers Best way to store currency values in C++ I've noticed that Visual Studio 2008 is placing square brackets around column names in sql. Do the brackets offer any advantage? When I hand code T-SQL I've never bothered with them.  Example:  Visual Studio:  SELECT [column1], [column2] etc...   My own way:  SELECT column1, column2 etc... How to get memory usage under Windows in C++ Combinatorial Proof Question: Vandermonde convolution identity I'm really iffy on combinatorial proofs in general and now that there is a sum, it's just confused me even more. Can someone try and walk me through this proof?  $$ \binom{m + n}{r} = \sum_{k=0}^r \binom{m}{k}\binom{n}{r - k} $$ "The pair was ..." or "the pair were ..." sudo apt update &amp;&amp; sudp apt upgrade -y now shows the error message E:The package linux-modules-5.4.0-56-generic needs to be reinstalled. But I can't find an archive for it.  and nothing proceeds. How can I fix this problem? Thanks. Before, the concept of imaginary numbers, the number $i = \sqrt{-1}$ was shown to have no solution among the numbers that we had. So we declared $i$ to be a new type of number. How come we don't do the same for other "impossible" equations, such as $x = x + 1$, or $x = 1/0$?  Edit: OK, a lot of people have said that a number $x$ such that $x = x + 1$ would break the rule that $0 \neq 1$. However, let's look at the extension from whole numbers to include negative numbers (yes, I said that I wasn't going to include this) by defining $-1$ to be the number such that $-1 + 1 = 0$. Note that this breaks the "rule" that "if $x \leq y$, then $ax \leq ay$", which was true for all $a, x, y$ before the introduction of negative numbers. So I'm not convinced that "That would break some obvious truth about all numbers" is necessarily an argument against this sort of thing. How to fully backup non-rooted devices? Posting and answering questions you have already found the answer to