On a default Ubuntu (15.04) installation, We have 7 TTYs that we can switch with Ctrl+Alt+F1 (or F2 - F7), where TTY1-6 are terminals and TTY7 is the graphical X session.  I would like to have more than one TTY with graphical login, so e.g. make TTY6 an additional GUI terminal.   Is this possible and if yes, how do I set it up and are there restrictions (like don't log into the same account graphically twice)? And when I manually start an x session in a TTY, how do I quit that graphical session again afterwards and revert the TTY back to a terminal?
I want to have more than one user logged on at the same time, on the same computer. Each user should have a full X session. It is easy enough to log in to multiple concurrent non-X Linux terminals, but I want the X factor. Maybe I've missed something, but I only see a Main Menu option to Log out of the current user, and nothing for Switch User. Is there a simple way to do this?
When searching on a site with  enabled (), I saw some  rendering issues: (and currently it's also in the )        Even though the LaTeX rendering is fine when opening the :        The LaTeX code is:  $f(n) = \begin{cases} 0,  &amp; \text{$ \omega&lt;0, \omega=1, \omega&gt;3 $} \\[2ex] -\omega + 1,  &amp; \text{$ 0\le\omega&lt;1 $} \\[2ex] \omega^2 - 1,  &amp; \text{$ 1&lt; \omega \le 2 $} \\[2ex] 3 \omega,  &amp; \text{$2 &lt; \omega \le 3 $} \end{cases}$ How to expand primary partition when WUBI is used to install? I have installed Ubunut 12.04 using WUBI. The "Installation size" options I chosen was 18GB i.e the amount of space you want to "give up" for WUBI. That is the space wubi's Ubuntu install is able to use. Wubi creates a disk image (loopmounted device) on your host system in/on which Ubuntu is installed. Now, I am running out of memory in primary partition.   Could anyone help me out to extend/stretch the partition size? How is a pitch supporting fast bowlers or spin bowlers? Alignment issue in Area 51 main site - site switcher, inbox and achievements How can I calculate how long it will take to transfer a file over LAN? I want to know about the method with which we can calculate data transfer speed.   If I am sending a 1 GB file through a 1 Gb/s LAN connection, from one computer to another, how much time will it take to transfer that file? Line numbering paragraph oriented? I'm using the lineno package with the pagewise option but I need a way to get the numbering restart every paragraph break. I need a general solution to pass to the latex command, e.g.:  latex "\AtBeginDocument{\RequirePackage[pagewise]{lineno}\linenumbers}\input{mydocument.tex}"   I read the lineno manual but the package does not provide this feature. Is there any trick to do that? How can I convert a string to boolean in JavaScript? LaTeXiT is cropping the pdf I am using LaTeXiT (pierre chachatelier, www.chachatelier.fr) - latex equation editor for Powerpoint for mac.  It's producing pdf that appear to be "cropped" on top (see attached) - I've tried already with changing the "margins" option (Preferences>General) but unsuccessfully - don't think that's the problem.   Any hint?   Thanks Replace arbitrary characters in the middle of an IP address string with sed I need to find and replace either one or two numerical characters in strings in a file.  The strings are IP addresses of the form:   10.xx.y.z    Where xx can be one or two characters.    I want to replace the xx with the single character 0, so I have  10.0.y.z    preserving the values of y and z.   The string may appear multiple times in the file.  What is the sed invocation to do this? I know how to use the subfig package to fit many subfigures (each with its own caption) into a larger figure (with a general caption).  I know how to use the sidecap package, the put a figure's caption on the side of the figure.  What I do not know is how to display a caption inside the figure, as if it were a subfigure.  More precisely, I have three subfigures that I would like to fit on a 2x2 layout, with the remaining quadrant used for the caption.    Is that easy to achieve? I've found a nasty VBS way to do this, but I'm looking for a native PoSh procedure to edit the properties of a .LNK file.  The goal is to reach out to remote machines, duplicate an existing shortcut with most of the correct properties, and edit a couple of them.  If it would just be easier to write a new shortcut file, that would work too. How do wizards cast spells which appear on their spell list when it has a divine focus component? What does a wizard do to cast a spell which contains a DF component? Take  for example,  Components V, S, DF    A divine focus component is an item of spiritual significance. The divine focus for a cleric or a paladin is a holy symbol appropriate to the character's faith. The divine focus for a druid or a ranger is a sprig of holly, or some other sacred plant. If the Components line includes F/DF or M/DF, the arcane version of the spell has a focus component or a material component (the abbreviation before the slash) and the divine version has a divine focus component (the abbreviation after the slash).  So do wizards have holy/unholy symbols in their spell components pouch or what? I'd love your help with finding the sign of the following integral: $\int_{0}^{2 \pi}\frac{\sin x}{x} dx$,I know that computing it is impossible.  I tried to use integration by parts and maybe to learn about the sign of each part and conclude something but It didn't work for me.  Any suggestions? Does a wireless-N (802.11n) network have poor performance when in b/g "mixed" mode? It seems to be an "old" wives tale that, when using a wireless-N router in "mixed mode" to support legacy 802.11b or 802.11g devices, the performance of 802.11n clients will suffer.      claim that when running in mixed-mode, all (some?) N clients run at G speeds.   make the same claim, but say it only happens when a G client is connected.    say N clients run faster, but still run about 30% slower than if the router were in N-only mode, even if there are no legacy B/G clients connected.    claim there is no speed drop for N clients when running on a mixed-mode network.  They say the only issue is that overall network throughput will be lower, because only one client can be transmitting at any time, so some of that transmission time must be shared with the legacy B/G clients running at lower speeds, reducing the overall throughput from what it would be if there were only N clients connected.    So, which is it?  Will running in mixed-mode slow down my network, even if there are no B/G clients?  If I'm running N, will having another client connected at B/G slow me down substantially vs. if they were running N? Would a 9V alkaline power a 12V DC motor? I am thinking about buying a 12V DC motor but want to keep everything, including the motor, battery, and power switch somewhat compact. I am not very knowledgeable about these kind of things and am curious whether or not my 12V DC motor would run at all on a 9V battery. Confusion about the definition of function Yesterday I was talking to one of my friends about the definition of function. The formal definition of function is given by Cartesian Products but my friend's question was whether it is possible to define a function without being acquainted with any concept of Cartesian Products.   To answer this question I told him the definition of a function may be given by defining a function $f$ from the set $X$ to $Y$, denoted by $f:X\to Y$, to be some "rule" (the word rule being an undefined concept) which associates, to each member of $X$, exactly one element of $Y$.     But my friend said that the definition using the concept of "rule" isn't rigorous and there are examples that don't obey the definition but still is a function in the Cartesian Product sense.    My questions are,   Why the definition of function using concepts such as "rule" isn't rigorous?  Is there really any example which doesn't obey the definition but still is a function in the Cartesian Product sense? Difference between block size and cluster size Do file-extensions have any purpose (for the operating system)? Linux determines the type of a file via a code in the file-header. It doesn't depend on file-extensions for to know which software is to use for opening the file.  That's what I remember from my education. Please correct me in case I'm wrong!  Working a bit with Ubuntu systems recently: I see a lot of files on the systems which have extensions like .sh, .txt, .o, .c  Now I'm wondering: Are these extensions are meant only for humans? So that one should get an idea what kind of file it is?  Or does they have some purpose for the operating-system too? Find $ P(Z>X+Y)$ where $X,Y,Z \sim U(0,1)$ independently I'm trying to follow a line in a derivation for $P(Z&gt;X+Y)$ where $X,Y,Z$ are independent continuous random variables distributed uniformly on $(0,1)$.  I've already derived the pdf of $X+Y$ using the convolution theorem, but there's a line in the answer that says:  $P(Z&gt;X+Y) = \mathbb{E}[\ P(Z&gt;X+Y\ |\  X+Y )\  ]$ where $\mathbb{E}$ is the expectation.  I'm not familiar with this result. Could anyone give a pointer to a similar result if one exists?  Thanks. Showing margins/frames in beamer slides