I installed linux ubuntu last month and everything got messed up . When I first tried it , everything works fine. It's fast and convenient so I decided to install it permanently but after permanently installing it , my computer hangs frequently and then one day, when I turned on my pc, the computer isn't logging in . Then there is this . . . GRUB Rescue > No Partition . Can I install windows again ? if yes then how ?
I have absolutely no experience with Linux, and I desperately need to get my computer back up and running again with Windows.  How do I remove Ubuntu and reinstall Windows?    Editor's note: many of the answers are about removing Ubuntu from dual-boot but keeping Windows (which is a bit complicated), while other answers are about removing Ubuntu from single-boot (which is easy: basically just format the disk while installing Windows). The question as written is ambiguous between dual-boot or single-boot.
Solving an equation over the reals: $ x^3 + 1 = 2\sqrt[3]{{2x - 1}}$ Solve the following equation over the reals:$$ x^3  + 1 = 2\sqrt[3]{{2x - 1}} $$ I noticed that 1 is a trivial solution, then I tried raising the equation to the 3rd, then dividing the polynomial by $(x-1)$.. But I can't see the solution, how do I go from here? I created a model and added some Actions in the DopeSheet editor (more or less 5).  I exported the model to my game engine, saved the .blend file (Ctrl-S) and closed it.  Then I opened it again, and all the actions were gone, it just had the one I was using last.  The same happens with some preferences (for example, I disabled mip-maps on User Preferences -> System, and I have to re-enable it every time I open the .blend file again.  Does somebody knows how to restore the Actions and save everything? Thanks. Can I visit the US for tourism on a previously unused B1/B2 visa? Note: This is NOT a duplicate of  Difference: In both other questions, the posters traveled once to the US for the original purpose for which the B1 visa was obtained. Their question is about visiting again using the same visa. However, I've not traveled to the US yet, and I'm planning my visit. What I want to understand whether I can use this visa for a visit whose purpose is not the same as what was submitted along with the application.  Can I use a B1/B2 visa for tourism that was originally obtained for business purposes BEFORE I actually visit the US even once? I had applied for a business visitor visa for a valid business reason but by the time I got it stamped, my plan changed. So I've not visited the US even once. Can I now use this visa to visit as a tourist without having used that visa for its original intended purpose? PS: I live in India. How to find relevant and new open research topics? How can one find relevant and new open research topics?  When working on my PhD thesis, I find it hard to find open questions in my very specific research area. Which approach do you take to find new and relevant topics? Short-cut for switching to a given directory In the Ubuntu terminal I find myself spending considerable time to switch to a particular directory every time the computer starts up. Is there some way I can make this process easier? Is there some hotkey or some quick directory change that I can use (like speed dial on a phone)?   eg:     cd 1:Changes to saved directory one Is there a difference between "write" and "write down"? I develop a windows application and am curious whether it works via Wine. The application runs fine with Wine but I get no sound. In fact, I'm not sure whether my ubuntu installation has MIDI capabilities. The sound output settings shows "LFE on Separate Mono Output" one with "no amplifier" and another with "amplifier". They both function. I am using Ubuntu 12.04 as a client on virtualbox that runs on windows 7.  Thanks for any suggestion!  EDIT: virtual box hosted by windows 7, ubuntu running as a client in virtualbox. I admit this feature request is probably somewhat limited in useful scope, but I'm throwing it out there anyway. Inspired by , and because I want to use it on , I'm requesting that name be supported on a tags in posts.  On very long answers, such as the closing/migration guidance answer, this would allow direct linking to the specific closure reason. This would then allow us, when someone , to link directly to the appropriate reason and description thereof.  I recognize the limited scope of this, however, I have seen other long answers that could stand to have that kind of "deep" linking ability as well.  (The original incarnation of this post had either name or id, but preferenced name. Per Koper's answer, which I agree with, I took out the idea of supporting id, because Koper's right -- too dangerous.) Let's say I have a node type "Article" which has a field "File" which is set to handle public files. A lot of articles and files get added.  Now the specs suddenly change and the "Article" will move behind a login and therefore also the attached files must be changed to be not publicly accessible anymore.  I already found out  pretty easily by reimporting the manually updated field.storage.node.field_file.yml config. But: this only affects new files that will be added after the switch. It doesn't work for existing files. They still are accessible publicly. Many thousand existing files would need to be manually reuploaded to also make them private.  Does anybody of you have solved that in D8 before? If so, then how?  As all I can think of right now is to programmatically query all "Article" nodes, then foreach through all nodes, get the files, temporarily store them somewhere else, empty the field out, then try to reupload the files programmatically (probably my next question) and then resave each node.  Does that sound reasonable? Or can you think of any other approach that might work here (in D8)? $|a_{n+1}-a_n| \leq \frac{1}{2} |a_{n}-a_{n-1}|$. I'm trying to show that $(a_n)$ is convergent by showing that $(a_n)$ is Cauchy.  let $|a_2 - a_1 |  =x$.   $|a_3-a_2| \leq \frac{1}{2}x$  $|a_4-a_3| \leq \frac{1}{2}|a_3-a_2|\leq \frac{1}{4}x$  In general, for every $n$:  $|a_{n+1}-a_n| \le \frac {1}{2^{n-1}}x$  Let $\epsilon &gt;0$  for every $m,n &gt; 0 $, say $m&gt;n$ the following holds:  $$|a_m-a_n| = |a_m-a_{m-1} + a_{m-1} - a_{m-2} \dots a_{n+1}- a_n| \le$$  $$|a_m-a_{m-1}| + |a_{m-1} - a_{m-2}| + \dots |a_{n+1}-a_n| \leq \frac{x}{2^{m-2}} + \frac{x}{2^{m-3}} + \dots + \frac{x }{2^{n-1}}$$.  I can say that for big enough $n,m$, $|a_m-a_n|&lt;\epsilon$ and therefore, this sequence is Cauchy? It sounds not good enough to me yet I don't know what else to do here. I have a spreadsheet in Google Docs with two data rows and lots of columns like so:    Is it possible to easily convert these rows into two columns and lots of rows (obviously retaining all information and formulas)? In other words, to something like this:   19.9.2009   967,15 €  28.9.2009   950,78 € 12.11.2009   942,03 € ..           ..   There's probably a neat mathematical term for such a conversion, but I don't remember which (matrix something?). Feel free to suggest a better name for the question.  Edit: To clarify, ultimately I want to get rid of the original (two row) version and continue working on the converted one. TRANSPOSE(), , got me very close but not quite there. I want the raw data in the transposed version, not cells that mirror the original ones. When your 10-year old boy says “It’s meta,” what does it mean? In what situation and of what sort of object they use this phrase? I asked about  a few days ago, quoting Maureen Dowd’s review of the movie, “J. Edgar” in New York Times.   I received six answers. But I still don’t get a clear idea of what “It’s meta” means because I don't understand (or have a total inability to comprehend) the concept of “self-referential.”   An answerer : “Meta in this fairly recent, casual context is supposed to mean self-referential, or recursive in some way. This is the sense in which my teenagers would use this term.”  So let me resubmit the question on “meta” in simpler format. When your teenager boy says “It’s (or this is) meta,” what does it mean? In what situation and of what sort of object they use this phrase?  I’m sorry for many users who lent me kind answers to my previous question. But I would like to get it fully on the meaning and usage of “it’s meta,” as a colloquial expression, not the meaning of meta as a prefix. "May" & "Might": What's the right context? I may not be coming in tomorrow...    I might not be coming in tomorrow...       When should I use "may" and "might"? import Excel sheets by name Presentation of SL$(n,\mathbb{Z}_p)$ I just visited  and noticed that my profile picture is not the same as on all other sites.  According to  the image will be synchronized when synchronizing the complete profile. I did that but the image is still the same.  Then I wanted to change the image in the Area51 profile directly - but I can only change to a gravatar image and can't use the new and fancy Stack Exchange image.  Is that a bug? What is syntax highlighting and how does it work? I noticed that sometimes my code gets highlighted in different colors when rendered.   What is syntax highlighting? How does it work? Why isn't my code being highlighted correctly? How do I report a bug or request a new language? How do I use syntax highlighting? What languages are currently available on Stack Exchange? What's the starting wealth for higher levels? The PHB only gives starting wealth for Level 1 PCs. Based on my experience in other games, specifically Pathfinder, I would expect to get more at higher levels. Where can I find an appropriate table or calculation? Onomatopoeia for disgust Should +1 and thanks comments be a declined flag? As a moderator for GD.SE I was always led to believe our role is to clean old comments as they are intended to be a temporary item depending on the level of context and if they add any benefit to an answer.  On SO I haven't had any issues or declines when I read old Q&amp;As and see +1 and thanks and flag.    However, on other sites when I read an old Q&amp;A and I see thanks or +1 I try to be courteous and flag them as I am aware moderators do get measured by their cleanup and I'm accustomed in doing so on SO but these flags are declined.    So this leads me to ask:   Should +1 and thanks comments be flagged and is the intended role of a comment still to be considered as temporary? What is the proper classification for a thanks or +1 comment if it should be flagged?   I didn't see any Q&amp;As on this topic after browsing the tags:   and searching led me to:  but that was several years old.