$\forall t \in \mathbb{R}, e^{i \alpha_n t} \rightarrow 1 \implies \alpha_n \rightarrow 0$?
If $e^{itx_n}$ converges for every $t\in\mathbb R$, then does $x_n$ converge?
How were hobbits created? How were hobbits created? I can't find any reference in The Silmarillion about this. Are they just men who have shrunken over generations or what? Is there any possibility of setting up two factor authentication (2FA) for Stack Exchange OpenID authentication?  I could just use my (already 2FA-enabled) Google account for Stack Exchange, but I would prefer to continue use Stack Exchange OpenID.  After  (which, I appreciate, didn't affect Stack Exchange, as you use IIS and Schannel, not OpenSSL), there have been a lot of recommendations to change passwords and to enable 2FA where possible.  So, what are the chances of a text-messaging-based or Google-Authenticator-based 2FA for Stack Exchange? How to draw circle, square, and triangle marks in TikZ picture? Why are my objects in all layers? How to grep for text in a file and display the paragraph that has the text? Below is the text in the file:  Pseudo name=Apple Code=42B state=fault  Pseudo name=Prance Code=43B state=good   I need to grep for "42B" and get the output from the above text like:   Pseudo name=Apple Code=42B state=fault   Does anyone have idea on how to achieve this using grep/awk/sed? Why are the solutions of polynomial equations so unconstrained over the quaternions? An $n$th-degree polynomial has at most $n$ distinct zeroes in the complex numbers.  But it may have an uncountable set of zeroes in the quaternions.  For example, $x^2+1$ has two zeroes in $\mathbb C$, but in $\mathbb H$, ${\bf i}\cos x + {\bf j}\sin x$ is a distinct zero of this polynomial for every $x$ in $[0, 2\pi)$, and obviously there are many other zeroes.  What is it about $\mathbb H$ that makes its behavior in this regard to be so different from the behavior of $\mathbb R$ and $\mathbb C$?  Is it simply because $\mathbb H$ is four-dimensional rather than two-dimensional? Are there any theorems that say when a ring will behave like $\mathbb H$ and when it will behave like $\mathbb C$?   Do all polynomials behave like this in $\mathbb H$? Or is this one unusual? How can one show there is no holomorphic function $f$ on the open unit disc $\mathbb{D}$ such that it extends continuously to $\frac{1}{z}$ on $\partial\mathbb{D}$? I mean $f$ takes value $\frac{1}{z}$ when $|z|=1$ and continuous here.  Thank you. Why do we need to discard one dummy variable? I have learned that, for creating a regression model, we have to take care of categorical variables by converting them into dummy variables. As an example, if, in our data set, there is a variable like location:   Location  ---------- Californian NY Florida   We have to convert them like:  1  0  0 0  1  0 0  0  1   However, it was suggested that we have to discard one dummy variable, no matter how many dummy variables are there.   Why do we need to discard one dummy variable? Array#each vs. Array#map Create SOAP envelope of XML and send it as HttpWebRequest to WebService I'd like to play Dragon Age Inquision in english instead of the language of my operating system, but it seems to default to that and I can't find a way to change it. I already tried setting the Origin client language to english, but that didn't change anything.  Where can I change the language for Dragon Age: Inquisition? Show that there is $\xi$ s.t. $f(\xi)=f\left(\xi+\frac{1}{n}\right)$ Let $f:[0,1]\to\mathbb{R}$ be continuous and $f(0)=f(1)$. Show that for any integer $n\geqslant 2$, there is $\xi\in(0,1)$ s.t.$f(\xi)=f\left(\xi+\frac{1}{n}\right).$  I think this requires the intermediate value theorem somewhere. Can I access constants in settings.py from templates in Django? I have some stuff in settings.py that I'd like to be able to access from a template, but I can't figure out how to do it. I already tried  {{CONSTANT_NAME}}   but that doesn't seem to work. Is this possible? No SA password. No SQL Server Management Studio. No OS authentication I have this problem.  I need to do some administrative tasks on a MS SQL Database using SA account.   OS authentication is not set. SQL Server Manager Manager Studio is not installed. I have no other admin database account. I do have access to a Windows admin account The only tools installed on the database server are as shown:     How can I activate OS authentication so I can log into the database an reset the SA password ? Number of possible permutations of n1 1's, n2 2's, n3 3's, n4 4's such that no two adjacent elements are same? Apache: Scammers point dozens of domain names at my dedicated IP. How to prevent this? For the sake of discussion, pretend that I have an Apache webserver which serves a website at www.example.org. This domain name resolves to the public IP address at 192.168.1.100 (pretend this is a public IP).  The discussion at  demonstrates that anyone can point their domain at my IP. Apache won't prevent this by default, but an administrator can deal with these one at a time through use of a blacklist.  However, it's becoming more common for scammers to register dozens of domains (or more) for use in a scam. I'm concerned about the following possible attack:   A scammer registers hundreds of domain names, and points them at my dedicated IP address. The scammer directs search engines at their scam domains, thus using my content to increase their standing in the search engines. Later, the scammer moves their domain names to point to their own servers which host a scam/porn, or a competing business, etc. thereby reaping the benefits of their standing in the search engines. Some of these domains might be used to in  as well. Profit!!   I believe I have seen scammers using this trick in the past, involving dozens of domains. We didn't realize the scam implications at the time, and assumed these were misconfigured domains.  Is there a term for this nefarious SEO trick? SEO masquerading? DNS Diversion?  How could I prevent this using Apache? I'm considering a "whitelist" fix based on using a default VirtualHosts, ServerNames &amp; ServerAliases so that Apache only responds to requests where these white-listed ServerNames appear in the "Host: " header. Everything else would be rejected (or redirected to a particular page). However, I am unsure if this is the best approach.  For example, I've configured the domain  to point at the IP for Serverfault.com. You can see the results here:  . I can't seem to find a few of the Stones, so, is there a list available with the location of all the stones? How do I remove directories that begin with a dot after my server was infected? My server had been infected and the attacker spread a bunch of .5randomletters folders around my file system, with malicious code inside of them. I want to search for all the folders that begin with a dot, review them and then remove them.  How can I do that? Optimal tiling of polygon using ArcGIS Desktop? I am trying to tile a polygon with a minimal number of fixed sized squares.  Currently I am creating a fishnet over my polygon then spatially joining the squares that intersect the polygon. This is not optimal.  Also note the squares can be shifted vertically/horizontally but not rotated.  My end goal: The polygon represents a clipped image and I want a tiling of the clipped image. Where each tile is 300px by 300px. Some overlap is fine if that makes the problem easier.  Current    Manually optimized    Are there any tools or algorithms that would help with this? I am proficient with Python and ArcMap.  The polygon was created from line features so I also have access to those segments. Maybe that would will help for generating the squares.  The entire polygon must be covered. biblatex in a nutshell (for beginners) Is there a 'biblatex in a nutshell' guide out there? I'd like if someone explained to me the essentials on how to use biblatex (what lines I have to write in my document, which files I have to have, how many times and what I have to compile), so then I can go to  to customise it further.