What is the significance of there being Nine Nazgul?
Why were there 3-7-9 Rings of Power?
What geometric object is given by this equation? What geometric object is given by this equation?  $x^2+y^2+z^2+2xy+2xz+2yz-x-y-z-6=0$  Maple says it's a hyperboloid of one sheet, but is there a way to show it without going the long way by using the principal axis theorem? Someone has pointed their domain (www.bomberball.net) to the same IP as my domain (www.kapparate.com) , and Google is now showing the former when searching for Kapparate, rather than the latter. What's the best way to block requests coming from www.bomberball.net ? The standard font packages make global changes to the fonts in my document. What if I want to use a particular font for just a portion of my text?   How do I find the right name of the font? How do I select the font? How do I restrict the scope of the font change?     There are separate answers for different flavors of TeX (quick links): How can I prevent my mail from being classified as spam? When sending or forwarding emails using a personal or company domain using a  website or email client, how do I prevent the email from being incorrectly marked as spam? What's the best way to animate an illustration for the web? I have a couple of illustrations done in Illustrator and I am planing to animate it for a website that I am working on, I've heard of  toolkit with flash, but is it the best way to go or is there another "better" way of doing it?  Here's an example of the kind of animations I am aiming for: Is it possible to install Windows from an external hard drive?  I have Windows XP installed on my laptop, and I want to remove it and install Windows 7.  My Windows 7 installation is in an .iso format on an external USB hard drive.  Is it possible to install it or will I need to put in a DVD before I start installing? I'm using 3d to speed up production of 2d graphics of machines and structures (which have a lot of straight lines, objects and little details repeated all over the place).  The goal is to have an isometric background image that repeats seamless. I set the camera with orthographic projection and 45° of rotation.    And manually cut the vertical borders in an image editor in the position where it repeats. Then I can do something like this:    Instead of cutting it manually every time I do a test, I would like to set the camera view position and height from Blender. Then I can render an already seamless repeated image.  Those two Empty objects in the boundaries are where the camera borders should be. However I have no clue how to accurately set up the camera in this case. How can I do this? Increment value based on grouped field Dividing polynomial $f(x)$ by $x-3$ and $x+6$ leaves respective remainders $7$ and $22$. What's the remainder upon dividing by $(x-3)(x+6)$? How to parse hex values into a uint? Unable to send mail to hotmail from rackspace cloud Differences Between Row Echelon and Reduced Row Echelon Let $$A =\begin{bmatrix} 1&amp;3&amp;-6&amp;2\\5&amp;12&amp;-24&amp;7\\9&amp;15&amp;-30&amp;6\end{bmatrix}$$  $$RREF(A) =\begin{bmatrix} 1&amp;0&amp;0&amp;-1\\0&amp;1&amp;-2&amp;-1\\0&amp;0&amp;0&amp;0\end{bmatrix}$$ $$REF(A) =\begin{bmatrix} 1&amp;3&amp;-6&amp;2\\0&amp;1&amp;-2&amp;1\\0&amp;0&amp;0&amp;0\\\end{bmatrix}$$  Now, provided this information, it can be found that the basis for the nullspace of $A$ using the $RREF(A)$ is: $$\begin{pmatrix} \begin{bmatrix} 0\\2\\1\\0 \end{bmatrix}, \begin{bmatrix} 1\\-1\\0\\1 \end{bmatrix}\end{pmatrix}$$  Using the $REF(A)$ the "basis" for the nullspace is:  $$\begin{pmatrix} \begin{bmatrix} 6\\2\\1\\0 \end{bmatrix}, \begin{bmatrix} -2\\-1\\0\\1 \end{bmatrix}\end{pmatrix}$$  Is the "basis" that I provided for the $REF(A)$ actually a basis? How does the  $REF$ and $RREF$ of a matrix differ? Add a "flag" button in the revision list How can I check if a single character appears in a string? How do I change a switched outlet to a half-hot outlet? I am trying to change a switched outlet to a half-hot outlet. If you can see the picture, the outlet currently only has a white, black, and ground wire coming to it.   The switch is on the other side of the wall and it would be eextremely difficult and ugly to run another wire to it. (no crawl or attic space). So my question is, can I change the current outlet/wiring within the outlet to make it a half-hot? My understanding is that removing the brass connector will just make half of it dead. Proving that if $A^n = 0$, then $I - A$ is invertible and $(I - A)^{-1} = I + A + \cdots + A^{n-1}$ How to Highlight a Row on Active Status I have a column which should define in list if the issue is in status: -Not Started, Active, Completed.   I would like to ideally add some colour to this by the row for example if completed it is green or active it is red. Then it highlights the whole row, do you know if this can be edited within the columns settings or if there any step by step instructions that can be followed to make this change? (ideally for someone new to sharepoint)  Thank You what could cause a script to fail to find python when it has `#!/usr/bin/env python` in the first line? Trying to get casperjs running on Ubuntu 12.04. After installing it when I run I get:   09:20 $ ll /usr/local/bin/casperjs lrwxrwxrwx 1 root root 26 Nov  6 16:49 /usr/local/bin/casperjs -&gt; /opt/casperjs/bin/casperjs  09:20 $ /usr/bin/env python --version Python 2.7.3  09:20 $ cat /opt/casperjs/bin/casperjs | head -4  #!/usr/bin/env python  import os import sys  09:20 $ casperjs : No such file or directory  09: 22 $ python Python 2.7.3 (default, Sep 26 2013, 20:03:06)  [GCC 4.6.3] on linux2   So Python is present and runnable, casperjs is pointing to the right place and it is a python script. But when I run it I get "No such file".   I can fix it by changing the first line of the casperjs python file from:    #!/usr/bin/env python   to:   #!/usr/bin/python   Result:   $ casperjs --version 1.1.0-DEV   I managed to fix it, but I'm wondering why it didn't work with #!/usr/bin/env python, since that seems to be a normal interpreter line. Do I have something configured wrong?   Here are the steps to get casperjs:   $ git clone git://github.com/n1k0/casperjs.git $ cd casperjs $ ln -sf `pwd`/bin/casperjs /usr/local/bin/casperjs $ casperjs : No such file or directory A sequence $\{x_j\}$ is said to be fast-Cauchy if $\sum_1^\infty d(x_j,x_{j+1})&lt;+\infty$. Show that every Cauchy sequence has a fast-Cauchy subsequence.   **My attempt:**Argue by contradiction, suppose there is no such subsequence. Then for any subsequence $\{{x_j}_k\}$,  $\sum_1^\infty d({x_j}_k,{x_j}_{k+1})$ diverges. Vaguely recall from an analysis course, if a series diverges, it doesn't not satisfy the Cauchy criterion. That is to say, there exists $\epsilon&gt;0$ such that for all $k$ and all $p\ge1$, $d({x_j}_{k+1},{x_j}_{k+2})+...+d({x_j}_{k+p}+{x_j}_{k+p+1})\ge\epsilon$.  Then I intuitively think that this is a contradiction, since if the original series is Cauchy, then after a large $N$, since $d(x_m,x_n)$ has to be very small, so that their sum should be smaller than given $\epsilon$, which is a contradiction. But I don't know how I can write down the concrete proof? I work at an embedded software company. This morning I found a USB stick in the parking lot in front of the building. With all the stories of "dropped USB stick attacks" in mind, I'm obviously not going to just plug it into my laptop. OTOH, I'm curious to know whether this was actually an attempt to compromise our systems, or it's really just an innocent case of somebody accidentally losing a USB stick. How do I safely inspect the USB stick without risking exposure?  I'm worried not just about malware and crafted file system images; there's also stuff like power surge attacks:.  EDIT: Many of the answers seem to assume I want to keep the drive and use it afterwards. I have no interest in that at all, I know USB sticks are cheap, and that it wouldn't be mine to keep anyway. I only want to know whether this was indeed a semi-targeted attack, partly out of curiosity whether this actually happens in real life and not just in security papers, but also so that I could warn my coworkers.  I want to know how I would figure out whether the stick contains malware. And that's not just a matter of looking at the drive contents and seeing a suspicious autorun.inf or a carefully crafted corrupt file system - I very much also want a way to inspect the firmware. I sort-of expected that there were tools for extracting that and comparing to known-good or known-bad binaries.