I'm using Ubuntu 12.04 LTS,and I have a laptop with good configuration. I would like to install windows 8/7 inside my Ubuntu OS. Is it possible? If yes, what is the process? Can I install it from DVD?
I have already dual systems : Windows 7 and Ubuntu installed on my laptop. The Windows 7 had been installed when I bought this laptop, and I don't have a CD.  I just installed VitrualBox under Ubuntu, hoping that I could install another Windows in this virtual machine, so that I could run some applications of Windows even under Ubuntu.  But it seems that I need a CD or ISO of Windows to boot inside this virtual machine. Otherwise, there is an error: FATAL: No bootable medium found! System halted. My question is where I could find a CD or ISO?  At the moment, I am downloading ISO from this , but do not know if it will work. By the way, I am not sure if I should pick the 32-bit or 64-bit? As my CPU is 64-bit but my Ubuntu is i386.  Could anyone help? Thank you very much.
Fibonacci numbers and proof by induction Consider the Fibonacci numbers $F(0) = 0; F(1)=1; F(n) = F(n-1) + F(n-2)$.  Prove by induction that for all $n&gt;0$,  $$F(n-1)\cdot F(n+1)- F(n)^2 = (-1)^n$$  I assume $P(n)$ is true and try to show $P(n+1)$ is true, but I got stuck with the algebra. How do we reach $P(n+1)$ from $P(n)$? Also, strong induction may be used instead. Can I make `find` return non-0 when no matching files are found? I have an Android phone which is connected to a secured Wi-Fi hotspot.  How can I find out the password of the hotspot from the phone? How to find architecture of my PC and Ubuntu? I am trying to plot the function 1/x^2 but the result is obviously wrong, here is how it looks like    here is the code  \begin{center}      \begin{tikzpicture}      \begin{axis}[      %xlabel=$x$,     %ylabel={$f(x) = x^2 - x +4$}   ]      \addplot[blue] {1/(x^2)};     \end{axis}     \end{tikzpicture} \end{center}   Any suggestions on how to fix this? ColdFusion adding extra quotes when constructing database queries in strings I am coding in ColdFusion, but trying to stay in cfscript, so I have a function that allows me to pass in a query to run it with   &lt;cfquery blah >   #query# &lt;/cfquery>   Somehow though, when I construct my queries with sql = "SELECT * FROM a WHERE b='#c#'"  and pass it in, ColdFusion has replaced the single quotes with 2 single quotes.  so it becomes  WHERE b=''c'' in the final query.  I have tried creating the strings a lot of different ways, but I cannot get it to leave just one quote.  Even doing a string replace has no effect.   Any idea why this is happening?  It is ruining my hopes of living in cfscript for the duration of this project Why shouldn't we use words such as 'here' and 'this' in textlinks? Over the years of surfing on the web I have found numerous examples of people saying that you shouldn't use the word "here" in a textlink etc. Personally I like the idea of using the word, because it is so straightforward for your visitors to know where to click.  The only reason that I can truly think of is for SEO purposes. The word here doesn't have much value as a keyword as such.  I would like to know some other opinions on why we should/shouldn't use word like "this" and "here" in a textlink. Long ago someone demonstrated the following card trick with a standard 52-card deck:  (1) A volunteer selects 5 cards from a shuffled deck, which the performer does not see.  (2) The assistant puts exactly 4 of those in a pile and passes it to the performer.  (3) The performer can then identify the 5th card.  There are a few ways to execute this trick, one of which goes as follows.  (1) The assistant finds a suit common to 2 of the 5 cards, with values $x$ and $y$ modulo $13$.  (2) He then removes one of them, say $x$, such that $x-y \in [1..6]$ modulo $13$.  (3) He then puts the other one at the top of the pile.  (4) And he puts the 3 other cards after that in a permutation corresponding to $x-y$ modulo $13$.  Since (1) works by pigeonhole, (2) works because $\frac{13-1}{2} = 6$, and (4) works because there are 6 possible permutations of 3 cards, the trick succeeds. My question is whether the same trick can work with more than 52 cards. It is not obvious to me how to do so, nor compute the maximum number of (pairwise distinct) cards possible. Also, it seems to me that even if the trick can be made to work for $n$ cards, it may not work for $n-1$ cards! Any ideas? How to open pdf file in Windows Phone 8? $\zeta_{15}$ is $15$th primitive $n$th root of unity.   Question: Find the structure of the group $Gal(\mathbb{Q}(\zeta_{15})/\mathbb{Q})$  I know that if $p$ is prime then $G=Gal(\mathbb{Q}(\zeta_{p})/\mathbb{Q})=\mathbb{Z_{p}}^*$ but when $p$ is not prime, I am not show how to solve this if not prime.  Does my required group have any relation to some cyclic group $\mathbb{Z_n}$, i.e. abelian  Would really appreciate your guidance as I have not got my head around these concepts of cyclotomic fields and Galois structure. Thanks In MTG, what happens when a player loses in multiplayer? In Magic: The Gathering, the rules for a player losing in a multiplayer game are quite complex, so I'd like to try to understand them by example. I would be happy to ask each of these situations as a separate question if that is preferred, but they all seem related, and I would love to have one place to look up all of these answers.  Let's say I'm playing with two friends, Bob and Chloe, in a simple free for all. Unfortunately, I lose. When I lose, suppose the following:   I controlled an  which has exiled Bob's , does he get his bear back? I have a  on the stack targeting Chloe, does Chloe take the 2 damage still? Earlier in the turn I cast  to prevent damage to one of Bob's . If it later takes 3 damage, will that damage be prevented? Something I controlled gave Bob a 1/1 soldier token. What happens to the token? Something Chloe controlled gave me a 1/1 soldier token. What happens to the token? I had a  enchanting one of Bob's army of . What happens to the bear? I had also played  on Bob's final . What happens to the last bear? Chloe had  my . What happens to the Clone? Are there any other situations specifically addressed by the rules? Regarding running Watir scripts for UI Automation from Jenkins CI - How to hook up Jenkins and watir-automations File has different name in terminal and Finder I've just downloaded the driver for my preferred trackball from Logitech. In the Finder, the Installer's filename is Logitech Control Center Installer.app. In the Terminal, ls shows LCC Installer.app. How did this happen? In a triangle $\angle A = 2\angle B$ iff $a^2 = b(b+c)$ Prove that in a triangle $ABC$, $\angle A = \angle 2B$, if and only if:  $$a^2 = b(b+c)$$  where $a, b, c$ are the sides opposite to $A, B, C$ respectively.   I attacked the problem using the Law of Sines, and tried to prove that if $\angle A$ was indeed equal to $2\angle B$ then the above equation would hold true. Then we can prove the converse of this to complete the proof.   From the Law of Sines,   $$a = 2R\sin A = 2R\sin (2B) = 4R\sin B\cos B$$  $$b = 2R\sin B$$  $$c = 2R\sin C = 2R\sin(180 - 3B) = 2R\sin(3B) = 2R(\sin B\cos(2B) + \sin(2B)\cos B)$$  $$=2R(\sin B(1 - 2\sin^2 B) +2\sin B\cos^2 B) = 2R(\sin B -2\sin^3 B + 2\sin B(1 - \sin^2B))$$  $$=\boxed{2R(3\sin B - 4\sin^3 B)}$$  Now,   $$\implies b(b+c) = 2R\sin B[2R\sin B + 2R(3\sin B - 4\sin^3 B)]$$  $$=4R^2\sin^2 B(1 + 3 - 4\sin^2 B)$$  $$=16R^2\sin^2 B\cos^2 B = a^2$$  Now, to prove the converse:  $$c = 2R\sin C = 2R\sin (180 - (A + B)) = 2R\sin(A+B) = 2R\sin A\cos B + 2R\sin B\cos A$$  $$a^2 = b(b+c)$$  $$\implies 4R^2\sin^2 A = 2R\sin B(2R\sin B + 2R\sin A\cos B + 2R\sin B\cos) $$  $$ = 4R^2\sin B(\sin B + \sin A\cos B + \sin B\cos A)$$  I have no idea how to proceed from here. I tried replacing $\sin A$ with $\sqrt{1 - \cos^2 B}$, but that doesn't yield any useful results. Borel set preserved by continuous map Let $f:\mathbb{R}^m\rightarrow\mathbb{R}^n$ be a continuous map. Show that if $A$ is a Borel subset of $\mathbb{R}^n$, then $f^{-1}(A)$ is a Borel subset of $\mathbb{R}^m$.   I know that for $A$ open subset of $\mathbb{R}^n$, then $f^{-1}(A)$ is open. Likewise for closed. A Borel subset is a countable unions/intersections of these sets, done repeatedly. From those facts, combined with $f^{-1}(A\cup B)=f^{-1}(A)\cup f^{-1}(B)$ and $f^{-1}(A\cap B)=f^{-1}(A)\cap f^{-1}(B)$, the statement should be intuitively true.  But to do it rigorously, I want to write $A$ as open and closed sets. But since the countable union/intersection can be done repeatedly, I don't know how I can write it that way. All of my Firefox add-ons have been disabled suddenly, how can I re-enable them? Changing console font on Ubuntu 10.04 Server How can I change local console font on Ubuntu 10.04 Server to Inconsolata? What early-2000s show about dimension hopping has a character who can swap limbs? An earlier question asked about a show that made me think of another one I can't remember.  It was a live action show about exploring different dimensions, and I think the main character was searching for his dad.  I remember seeing it in the US, but I don't know if it was limited to that.  I'm a little fuzzy on the details, but I think the main character could swap his limbs or something like that. I am trying to update Xcode to 8.0. My OS is 10.11.6 El Capitan. However I am getting:     We could not complete your update   There is not enough disk space available to install the product.   I have got 14.22 GB free space. How much do I need?  UPDATE: I do not know the exact figure, though I did manage to update with 17.21 GB free space later on. Realtek RTL8723be doesn't have good reception Only when I'm closer to the router, it shows any signal, but when I'm just little far from it, it is not showing wifi routers signals.