I currently have two partitions on one hard drive. Windows 7 is installed on partition C, and Ubuntu is installed on partition D.  I wish to format the Windows Partition and replace windows 7 with windows 8.1. Ubuntu wasn't installed with Wubi.  Will Ubuntu be ok ?
I installed Windows 7, which ate Ubuntu's boot file. When starting up the computer, it now goes straight to Windows, without giving me the option of booting Ubuntu.   How can I get Ubuntu back?
Consider the sequence defined by $a_1 = \sqrt{2}$, $a_2 = \sqrt{2 + \sqrt{2}}$, so that in general, $a_n = \sqrt{2 + a_{n - 1}}$ for $n &gt; 1$. I know 2 is an upper bound of this sequence (I proved this by induction). Is there a way to show that this sequence converges to 2? What I think is that the key step is to prove 2 is the least upper bound of this sequence. But how? C# HttpWebRequest with XML Structured Data Does separation of variables in PDEs give a general solution? When a partial differential equation is solved using the separation of variables method, is the produced solution the most general one that satisfies the equation or have we lost some forms of the solution because of the assumption that it is in the form of separated variables? How do I stop the excel file being in use? I'm opening an Excel file and I'm getting the File in use pop-up that says it's locked for editing by me. However, I've not got it open on this computer (I think I had it open and my machine blue-screened). How do I go about fixing this?  Should specify, this is a file on a file share.  edit I'm not talking about if this is being used by another user on another machine, this is only accessible by me on this file share. What is the non-parametric equivalent of a two-way ANOVA that can include interactions? Hi I am trying to find the non-parametric equivalent of a two-way ANOVA (3x4 design) which is capable of including interactions. From my reading in Zar 1984 "Biostatistical analysis" this is possible using a method put forth in Scheirer, Ray, and Hare (1976), however, according to other posts online it was inferred that this method is no longer appropriate (if it ever was).  Does anyone know what method would be appropriate for doing so, and if so the corresponding functions in R or Stata? I'm looking for a good way to perform multi-row inserts into an Oracle 9 database.  The following works in MySQL but doesn't seem to be supported in Oracle.  INSERT INTO TMP_DIM_EXCH_RT  (EXCH_WH_KEY,   EXCH_NAT_KEY,   EXCH_DATE, EXCH_RATE,   FROM_CURCY_CD,   TO_CURCY_CD,   EXCH_EFF_DATE,   EXCH_EFF_END_DATE,   EXCH_LAST_UPDATED_DATE)  VALUES     (1, 1, '28-AUG-2008', 109.49, 'USD', 'JPY', '28-AUG-2008', '28-AUG-2008', '28-AUG-2008'),     (2, 1, '28-AUG-2008', .54, 'USD', 'GBP', '28-AUG-2008', '28-AUG-2008', '28-AUG-2008'),     (3, 1, '28-AUG-2008', 1.05, 'USD', 'CAD', '28-AUG-2008', '28-AUG-2008', '28-AUG-2008'),     (4, 1, '28-AUG-2008', .68, 'USD', 'EUR', '28-AUG-2008', '28-AUG-2008', '28-AUG-2008'),     (5, 1, '28-AUG-2008', 1.16, 'USD', 'AUD', '28-AUG-2008', '28-AUG-2008', '28-AUG-2008'),     (6, 1, '28-AUG-2008', 7.81, 'USD', 'HKD', '28-AUG-2008', '28-AUG-2008', '28-AUG-2008'); Is there a regular expression to detect a valid regular expression? Is it possible to detect a valid regular expression with another regular expression?  If so please give example code below. Is there a cross-browser onload event when clicking the back button? For all major browsers (except IE), the JavaScript onload event doesn’t fire when the page loads as a result of a back button operation — it only fires when the page is first loaded.  Can someone point me at some sample cross-browser code (Firefox, Opera, Safari, IE, …) that solves this problem? I’m familiar with Firefox’s pageshow event but unfortunately neither Opera nor Safari implement this. Why did the descriptive "Orientals" shift into a pejorative? Automatically add vertical space /only/ between two sequential paragraphs I am using KOMA-script scrreprt class.  I know I can use \usepackage{parskip} or \setlength{\parskip}{12pt}, but both of these also affect headings.  Adding \vspace{12pt} manually between all two sequential paragraphs seems to work, but that's anything but convenient. Is there a way to automate it? Taking screenshot of a specific area from the command line The book Theory of Functions of a Real Variable by I. P. Natanson, proves that a denumerable or finite union of pairwise disjoint sets of cardinality $c$ has cardinality $c$.  The proofs given in the book are fairly easy, using the axiom of choice. But then it is left as an exercise a generalization of the above theorems for not necessarily pairwise disjoint sets.  I have searched all over the web, but all the proofs found so far are for pairwise disjoint sets.  The proof given in the book relies on the fact that each set $A_k$ can be matched with a set like $[a_{k-1},a_k)$, with $a_k$ point of a partition of $[0,1]$, such that $\bigcup_{k=1}^{\infty\lor n}A_k=[0,1)$. So it is easy to guess the bijective function, but I can't generalize this proof.  Any help is highly appreciated. Thanks and regards. What library do I have to use such that the document can render \lt and \gt as less than and greater than signs, respectively? \documentclass{article} %\usepackage{amsmath} It does Not work ! \begin{document} \[ x\lt y \gt z \] \end{document}  What library do I have to use such that the document can render \lt and \gt as less than and greater than signs, respectively? Edit I am using MathJax library in my site under Asp.net Mvc 3. Web application is vulnerable to XSS and XSRF attacks so &lt; and &gt; should be avoided as the input from the users. My database will save LaTeX commands that can be rendered by both LaTeX compiler and MathJax. Therefore, I need \gt and \lt that already work in MathJax. Source:  Rendered: Reading Excel files from C# I need to start by stating that I have read through every single problem on here relating to mine, but all of them seem to have access somehow to their server's files. I do not, so here is my question.  I'm on centOS 6.5 and ssh closes connection right after a successful login. I am using mac and windows/putty to access my server with the same results. Is there anyway I can access my server now without having access to its files?   Below is the readout from ssh -vvv right after a successful login:  debug1: Authentication succeeded (password). Authenticated to 4X.5X.XX.2 ([4X.5X.XX.2]:82). debug1: channel 0: new [client-session] debug3: ssh_session2_open: channel_new: 0 debug2: channel 0: send open debug1: Requesting no-more-sessions@openssh.com debug1: Entering interactive session. debug2: callback start debug2: fd 3 setting TCP_NODELAY debug3: ssh_packet_set_tos: set IP_TOS 0x10 debug2: client_session2_setup: id 0 debug2: channel 0: request pty-req confirm 1 debug1: Sending environment. debug3: Ignored env TERM_PROGRAM debug3: Ignored env SHELL debug3: Ignored env TERM debug3: Ignored env TMPDIR debug3: Ignored env Apple_PubSub_Socket_Render debug3: Ignored env TERM_PROGRAM_VERSION debug3: Ignored env TERM_SESSION_ID debug3: Ignored env USER debug3: Ignored env SSH_AUTH_SOCK debug3: Ignored env __CF_USER_TEXT_ENCODING debug3: Ignored env PATH debug3: Ignored env PWD debug1: Sending env LANG = en_US.UTF-8 debug2: channel 0: request env confirm 0 debug3: Ignored env XPC_FLAGS debug3: Ignored env XPC_SERVICE_NAME debug3: Ignored env SHLVL debug3: Ignored env HOME debug3: Ignored env LOGNAME debug3: Ignored env _ debug2: channel 0: request shell confirm 1 debug2: callback done debug2: channel 0: open confirm rwindow 0 rmax 32768 debug2: channel_input_status_confirm: type 99 id 0 debug2: PTY allocation request accepted on channel 0 debug2: channel 0: rcvd adjust 2097152 debug2: channel_input_status_confirm: type 99 id 0 debug2: shell request accepted on channel 0 Last login: Wed Oct  7 06:23:21 2015 from 1XX.XXX.X1.185 debug1: client_input_channel_req: channel 0 rtype exit-status reply 0 debug1: client_input_channel_req: channel 0 rtype eow@openssh.com reply 0 debug2: channel 0: rcvd eow debug2: channel 0: close_read debug2: channel 0: input open -&gt; closed debug2: channel 0: rcvd eof debug2: channel 0: output open -&gt; drain debug2: channel 0: obuf empty debug2: channel 0: close_write debug2: channel 0: output drain -&gt; closed debug2: channel 0: rcvd close debug3: channel 0: will not send data after close debug2: channel 0: almost dead debug2: channel 0: gc: notify user debug2: channel 0: gc: user detached debug2: channel 0: send close debug2: channel 0: is dead debug2: channel 0: garbage collecting debug1: channel 0: free: client-session, nchannels 1 debug3: channel 0: status: The following connections are open:   #0 client-session (t4 r0 i3/0 o3/0 fd -1/-1 cc -1)  Connection to 4X.5X.XX.2 closed. Transferred: sent 3176, received 2640 bytes, in 0.3 seconds Bytes per second: sent 10370.6, received 8620.4 debug1: Exit status 254 Embedding videos and animations I'm aware that it's possible to embed some kinds of videos and animations in LaTeX files (using the beamer or prosper classes) but I couldn't locate good documentation on this. My web searches returned a list of scattered forum questions and answers.   Could anybody give a link to some help or documentation page that systematically deals with the various ways of embedding videos and animations, the file types that work, etc.? Why is a normal subgroup of $G_1\times G_2$ with trivial intersections with $G_1$ and $G_2$ is abelian? Let $G=G_1\times G_2$ be a direct product, and let $H\triangleleft G$ be a normal subgroup such that $H\cap G_1=H\cap G_2=\{1\}.$ Then $H$ is abelian.     I considered the commutators of two elements in $H$, trying to show that it must be $1,$ but I don't see how this works. Any hint is very welcomed and appreciated. Thanks in advance. GRUB2 does not show Windows 8 option to boot into after Dual Boot Yesterday, I tried to dualboot Ubuntu 16.04 onto my hard drive, creating a new partition for Ubuntu alongside my existing Windows 8. First, I disabled the fast-boot option in Windows 8, and still GRUB did not load, and it went directly to Windows boot-up. Then I did some research and found this article:     Basically, I issued the BCDEdit command in Windows, and entered in the following code:  bcdedit /set {bootmgr} path \EFI\ubuntu\grubx64.efi   When I reboot, I get a basic GRUB2 terminal, and after I type in the exit command, then a second Shell prompt appears, and after typing the exit command again, the GRUB2 menu to select the OS to boot finally appears... with only Ubuntu and Ubuntu memory test as options, not Windows 8.  After booting into Ubuntu, I tried to run the Boot-repair Utility, but that shows this following error:   How do I approach this problem? The Pastebin log is here:   Thanks for the help! How Do You Select Only Part Of a Timeline To Be Rendered? Let's say I only want a section of the timeline to be rendered, and I want the final output to be in RAW AVI format.  How would you do that? Thanks guys! Which browsers are officially supported, and what else do I need? Which browsers are officially supported by Stack Exchange?  Also, what else is needed in order to use every feature of the site?