I have come across need to do something and need do something. My question is what's the difference between each other? My grammar book doesn't mention it
The verbs dare and need do not require auxiliaries when used in the interrogative; for example, “need I?” is as acceptable as “do I need?”  Excluding the auxiliaries themselves (like be, do, have), are there any other such verbs that work that way?
Best way to detect when a user leaves a web page? What is the best way to detect if a user leaves a web page?  The onunload JavaScript event doesn't work every time (the HTTP request takes longer than the time required to terminate the browser).  Creating one will probably be blocked by current browsers. Did Daenerys mess up regarding caravans? How do I find my follower if and when they leave me? I'm attempting to install Ubuntu 14.04.1 (the only version I have handy) onto my old Compaq Presario R3000 (this Ubuntu was recommended for this computer). The installation has stalled at about 60% and hasn't moved in an hour.  The message at the bottom says: Configuring bcmwl-kernal-source (i386).  I have no experience with Ubuntu (or with Linux, for that matter), coming from a strictly-Windows background). Can anyone offer some advice? What kind of material is the Robert Downey Jr. Iron Man's armor supposed to be made from? I know he crafted the prototype from the things he had on hand, but once he was able to build the next one(s) in his own lab, what hi-tech material did he use for the movie armor? I'd like to copy files from one external drive to a network connected drive. I want to make sure that there are no errors.  I know of MD5 hash files that I see for large single files that are download from the internet. I also know that I can use the terminal to 'diff' the two sets of files.  However, I'm looking for a piece of software that could confirm that all the files in the file structure have been copied by the finder completely, or a piece of software that would do the copying for me and confirm that all the bits are exactly the same.  The files are video related - and are often over a TB in size (not in one file - complex multi-folder nested files)  I'm fine if there is a terminal command that can do the copy and compare for me as well. (although being able to see the amount of time left on a copy is a very nice feature... additionally, I want to make sure I get ALL of the file - resource forks and all) In the simple linear regression case $y=\beta_0+\beta_1x$, you can derive the least square estimator $\hat\beta_1=\frac{\sum(x_i-\bar x)(y_i-\bar y)}{\sum(x_i-\bar x)^2}$ such that you don't have to know $\hat\beta_0$ to estimate $\hat\beta_1$  Suppose I have $y=\beta_1x_1+\beta_2x_2$, how do I derive $\hat\beta_1$ without estimating $\hat\beta_2$? or is this not possible? How to print only defined variables (shell and/or environment variables) in bash The bash builtin command set, if invoked without arguments, will print all shell and environment variables, but also all defined functions. This makes the output unusable for humans and difficult to grep.  How can I make the bash builtin command set print only the variables and not the functions?  Are there other commands which prints only the shell variables, without the functions?  Note: bash differentiates between shell variables and environment variables. see here Poincaré's theorem about groups Correct interpretation of a "double-negative" in American Pop Culture (i.e. "I ain't afraid of no ghost!") "(CRON) info (No MTA installed, discarding output)" error in the syslog plotting 3d points: z-axis is squashed Set spawn point for a specific player I made a server and me and one of my friends want to do a prank on another friend, because he stole all my enchanted diamond armor.  The Prank  I want to set a player's spawn point in a pit of lava, how would I do this without affecting anyone else's spawn point? Another simple series convergence question: $\sum\limits_{n=3}^\infty \frac1{n (\ln n)\ln(\ln n)}$ I'm being asked to determine if $\displaystyle\sum\limits_{n=3}^\infty \frac1{n (\ln n)\ln(\ln n)}$ converges. So, using Cauchy's Condensation Test, I reduced the problem to one of determining the convergence of $\displaystyle\sum\limits_{n=3}^\infty\frac 1{n\ln (n\ln 2)}$. Am I on the right path, and how do I proceed from here? Why is the relationship between atomic number and density not linear? fontenc changes sans serif bold font in KOMA-script Consider the following MWE:  \documentclass{article} %\usepackage[T1]{fontenc}  \begin{document}  \textbf{\textsf{Some text}}  \end{document}   The output of the above code is     and doesn't change if I uncomment the line  %\usepackage[T1]{fontenc}   Consider now the following MWE with scrartcl class instead of article:  \documentclass{scrartcl} %\usepackage[T1]{fontenc}  \begin{document}  \section{A section} \textsf{Some text} \end{document}      Uncommenting the line  %\usepackage[T1]{fontenc}   you get    As you can see, the sans serif font of the title is less  bold than without fontenc, while the normal text is not changed.  Does fontenc, combined with a KOMA-script class, load a different sans serif font, but only for bold face? Eclipse says: “Workspace in use or cannot be created, chose a different one.” How do I unlock a workspace? If directory is empty do this, If directory is not empty do that How can I disable the Windows key from opening the Activities overview? How can I disable the Windows key (or Super) from showing the GNOME Shell Activities overlay? I'm trying to factorise $$ x^3z - x^3y - y^3z + yz^3 + xy^3 - xz^3 $$ into four linear factors.  By plugging it into WolframAlpha I've learned that it's $$-(x-y)(x-z)(y-z)(x+y+z)$$  My question is: what are the steps involved in factorising the expression? Is there a method I don't know about that I'd have access to with my limited maths?  Really appreciate any help!