How to select the operating system to start first on a dual-boot installation How to select which operating system starts first on a dual-boot installation (Windows7 and Ubuntu 12.04)
How do I change the GRUB boot order? I have both Windows 7 and Ubuntu installed on a shared machine. Because a lot of the non-developers use Windows, I'd like to change the boot order to make it easier for them.  Currently the boot order looks like the following:   Ubuntu 11.10 kernelgeneric *86 Ubuntu 11.10 kernelgeneric *86 (safe boot)  Memory test Memory test Windows 7 on /dev/sda6   How do I change the default order so that Windows 7 is at the top of the list?   Windows 7 on /dev/sda6 Ubuntu 11.10 kernelgeneric *86 Ubuntu 11.10 kernelgeneric *86 (safe boot)  Memory test Memory test
Thailand visa exemption: any rule limiting number of entries per year? How can I make an X-Y scatter plot with histograms next to the X-Y axes? TV show that starts with debris encompassing Earth How to ignore the first line of data when processing CSV data? Proving by induction that $1^3 + 2^3 + 3^3 + \ldots + n^3 = \left[\frac{n(n+1)}{2}\right]^2$ Need guidance on this proof by mathematical induction. I am new to this type of math and don't know how exactly to get started.   $$ 1^3  +  2^3  +  3^3  +  \ldots  +  n^3  =  \left[\frac{n(n+1)}{2}\right]^2 $$ If $p$ is a prime and $p \mid ab$, then $p \mid a$ or $p \mid b$. The proof is already given in the textbook but I tried other way around.   Proof by contradiction: Let's assume that $p$ doesn't divide $a$ and $p$ doesn't divide $b$, but $p$ divides $ab$. So $\gcd(p,a)=1$ and $\gcd(p,b)=1$. Given that we can construct linear combinations   $sp+ta=1$ together with $up+wb=1$. Multiplying the left and the right sides of the equations we get  $spup+spwb+taup+tawb=1$ or $p(sup+swb+tau)+ab(tw)=1 \implies \gcd(p,ab)=1$. This is a contradiction.   Is it rigorous and sound proof? Get date for monday and friday for the current week (PHP) $$\sqrt{x + \sqrt{x + \sqrt{x + \cdots}}}= 5$$ Let's say you have a few expressions like the following:  $$\begin{array}((x+17)^2 \\ x^2 + 34x + 289 \end{array} \\ 288 + \frac{x^2}{2} + \frac{x^2}{2} + 34x + 1 \\ [...] $$  You get the idea: there's an infinite number of ways of representing the same expression. The challenge is that my application is validating answers to math problems, input by math students practicing a certain concept. I'd like to make sure that whenever they submit an answer, the checker is completely insensitive to the issues of ordering, simplification, formatting etc. which would be plain frustrating. I'd also ideally like to support more than one variable such as x, y, z in the same expression.  What's a reliable way to check that two expressions are the same? The most brute force way I can think of would be to just plug a number into each variable of each expression and see what the result is.  I have a hunch however that there might be ways of getting false positives this way. That, and I might be either missing something really obvious about this, or there might be a better way of doing the comparison.  Would love to hear what you think. Will inverse functions, and functions always meet at the line $y=x$? If I have a function, the inverse function, by definition will be a reflection of the original function in the line $y=x$, so if I wanted to find the point of intersection, instead of solving it with equating both of the functions to equaling each other, could I assume that the point of intersection, between the two functions, will always be at the point $y=x$? This would enable me to solve problems much easier, instead of having to solve quartic equations, for example. Every retraction is a quotient map? I have to proof that every retraction is a quotient map.. I have no idea where to start or what to use! A retraction $r:X \rightarrow A$  is a continuous map s.t. $r(a)=a$ for every $a\in A$. This might be a completely wrong question, but this is bothering me since many days ago. Given the mass (Sun) curves the space around it, gravitation is the result of such curved space (Correct me if I am wrong, source: A Documentary film). Given any point on a circle with center same as center of the mass, curvature in the space should be equal (Intuition).   Planets rotate around the Sun because of the curve in the space they should follow a circular path and the distance between planet and Sun should be at a distance.  Given the fact that earth has a elliptical orbit around the sun, and the distance between Earth and Sun varies according to position of the earth. Why do we have a elliptical orbit not a circular orbit. generic function with a "has property X" constraint? Unable to make recursive call in Javascript Regex to validate date format dd/mm/yyyy How can I convert byte size into a human-readable format in Java? What is a contrast matrix? What exactly is contrast matrix (a term, pertaining to an analysis with categorical predictors) and how exactly is contrast matrix specified? I.e. what are columns, what are rows, what are the constraints on that matrix and what does number in column j and row i mean? I tried to look into the docs and web but it seems that everyone uses it yet there's no defition anywhere. I could backward-engineer the available pre-defined contrasts, but I think the definition should be available without that.  &gt; contr.treatment(4)   2 3 4 1 0 0 0 2 1 0 0 3 0 1 0 4 0 0 1 &gt; contr.sum(4)   [,1] [,2] [,3] 1    1    0    0 2    0    1    0 3    0    0    1 4   -1   -1   -1 &gt; contr.helmert(4)   [,1] [,2] [,3] 1   -1   -1   -1 2    1   -1   -1 3    0    2   -1 4    0    0    3 &gt; contr.SAS(4)   1 2 3 1 1 0 0 2 0 1 0 3 0 0 1 4 0 0 0 Keyboard key stuck or not being recognized; how to fix This is an attempt to write a canonical QA for this issue, as per the Meta post:   I expect it to be periodically edited with the goal of becoming a comprehensive information resource.  I have a MacBook Pro that has a key(Shift, Return,   Command, P, etc.) that doesn’t respond when pressed or is stuck in the down position.    It's possible that my favorite beverage was spilled (or some other liquid damage).  It's also possible that I have no idea what happened.  It was working yesterday and suddenly today it's no longer working.  Is there any way to bypass or remap the key?  Can I  have the system ignore it completely?  (This question can also apply to external USB keyboards or the Bluetooth keyboards) How can I dynamically load the functions of java.lang.Math Can we prevent titles with an unnecessary tag in them?