Finding a group that spans a vector space of Polynomials
Finding a basis for a certain vector space of periodic polynomials
Setting the editing style on a UITableViewCell Is it possible to use a spell scroll with a spell that requires a bonus action to cast? The DMG contains spell scrolls (on page 200), with the following rule:     If the spell is on your class's spell list, you can use an action to read the scroll and cast its spell without having to provide any of the spell's components.   This is all well and good for spells with a casting time of 1 action (which admittedly is most of them), but for spells with a bonus action casting time, how is it supposed to work?  Does it require:   Both an action and a bonus action?  Just an action? Just a bonus action? Something else I haven't thought of?   In case it needs saying, I'm not interested in speculation here - only RAW-based answers or explicit statements of developer intent should apply. is a light side power that many Jedi, including  are capable of. In Episode I, Qui-Gon uses it twice (once to outrun droids and once on Jar Jar's tongue), Obi-Wan uses it once and Anakin uses high speed reflexes for the entire duration of the pod race with no formal training.  According to  the power has a high drain and requires a longer recovery period than other powers. And then of course there are hilarious drawbacks such as .  But why wasn't this power used in the following scenarios (and many, many others):   The Redshirt Jedi who accompanied Windu to arrest Palpatine, before they were summarily dispatched to the Nether. Qui-Gonn, to avoid a lightsaber through his gut. Yoda, to avoid flying senate seats. By Windu, who is supposedly a notable practitioner. I've taken some stock photography of lots of clear bottles, and now want to remove the background (which is white-ish, because at a pinch I could leave it...) so that the bottle becomes transparent with highlighting.  My bottles are clear with different colored liquids with multiple refraction and reflection surfaces.  I am looking for a background color subtraction effect that will allow me to get to transparent (hopefully with some sort of effect/opacity slider).  Ideas that I can't pull off yet:   Combine layer with a color fill layer (keyed off the "transparent color") in some manner to produce some output that could be used as the starting point of a layer mask Same layer combination as above, but somehow translating "pure white" to transparency.   Notes for what doesn't work (Photoshop terminology):   "Color Range" and delete (fuzzy select, but not graded/alpha) - results in harsh lines and only leaves the pure white and dark highlights and shadow refractions/reflections Magic wand selections for the same reason "Background Eraser" because although it is able to only subtract a certain color and leave "the rest", it (like all tolerance based tools) eventually hits a colour slightly outside of the range that it just won't touch.   I'll add more if I can remember what I've found This seems to be a chicken-egg problem. The most common task using sudo is installing and removing software.  sudo apt-get purge &lt;appname&gt;   But sudo itself can be removed.  sudo apt-get purge sudo # Do not run this command on production computers!   This is where the fun comes  ubuntu@ubuntu:~$ sudo bash: /usr/bin/sudo: No such file or directory   Although it's obvious that no person in his right mind will purge sudo (other than me), someone can be fooled to run this command (not directly, in its hex mode, or whatever it's called) or a person could SSH in disguised as tech guru and do the mess.  So is there a way of reinstalling sudo? Database design help. many-to-many relationship Sum of digits of repunits How do I parse command line arguments in Java? MikTeX 2.9, install packages on the fly? What is divergence? How to show that $x^4+1$ is irreducible in $\mathbb Z[x]$ but it is reducible modulo every prime $p$?   For example I know that $x^4+1=(x+1)^4\bmod 2$. Also $\bmod 3$ we have that $0,1,2$ are not solutions of $x^4+1=0$ then if it is reducible the factors are of degree $2$. This gives that $x^4+1=(x^2+ax+b)(x^2+cx+d)$ and solving this system of equations $\bmod 3$  gives that $x^4+1=(x^2+x+2) (x^2+2x+2) \pmod 3$. But is there a simpler method to factor $x^4+1$ modulo a prime $p$? I have an Ubuntu 14.04 server that has no external monitor connected.  I use NoMachine to remote control the machine.  When I do so, the Unity/Gnome interface doesn't see any monitors connected, so I can only use 800x600 when connecting with NoMachine.  If I plug in a monitor, I can set the resolution to whatever size the NoMachine window is on the remote computer.  Is there a way to create a "fake" monitor device on Ubuntu so I can set a desktop resolution in Unity/Gnome? Can a ultracentrifuge be used to test general relativity? With today's ultracentrifuge technology, they can spin so fast that the sample can be subjected to  accelerations of up to 2 millions Gs. That is equivalent to two solar masses. Has someone tried to measure the time dilation in a radioactive sample? How calculate that time dilation respect to the time outside the ultracentrifuge, for example one week. I think that that time dilation will be significant enough to be measured. Low-res texture blurry I unwrapped a simple plane and applied the following 80x80 pixel picture:    Yes, it's quite small. The problem is, the result is all blurry, like so:    How do I make it accurate to the pixel? USB is a popular standard and I was wondering whether there is some way to connect two or more computers using USB ports rather than the Ethernet ports. Is it possible to extend a tourist Schengen visa (12 more days)? My daughter applied at the Italian Consulate in Philadelphia, and they gave her two entries for 20 days (we thought it was for 20 days each entry). She was in Italy 12 days, then went to England for 1 week and flew to Venice to take a 10-day cruise. She couldn't make it because they said she has only 8 remaining days, but she still has a land tour already paid this week.  What can she do? Can she extend the Schengen visa for 12 more days? Right now, she is in Madrid, but next week she has to fly from Barcelona to Paris to start with the tour. What would happen if she decides to take the tour with the expired visa? She is a US permanent resident. Solve for $f(x)$ if $f(f(x))=6x-f(x)$ If $f: [0,\infty) \rightarrow [0,\infty)$ and   $f(f(x))=6x-f(x)$ $f(x)&gt;0$ $  \forall x \in (0,\infty) $   Find f(x) $ac\equiv bc \pmod{\!m}\!\!\iff\!\! a\equiv b \pmod{\!\!\frac{m}{(c,m)}}$ [Euclid's Lemma, congruence form] I came across this theorem:   For all integers a,b,c and m&gt;0, if d = GCD(c,m) then a*c ≡ b*c (mod m) iff a ≡ b (mod m/d).  The =&gt;proof states this:  a*c ≡ b*c (mod m) =&gt; m|(a-b)*c                    =&gt; m/d | (a-b)*c/d                   =&gt; m/d | (a-b)                   =&gt; a ≡ b (mod m/d)   I don't understand how to go from step 2 to step 3. The proof states that this is possible because m/d and c/d are coprime. To me this means GCD(m/d, c/d) = 1 but how does this cancel out the whole term? I have a set of 10 tables and each has an extra column that I don't want. Specifically, these tables are descriptions of database tables exported by phpMyAdmin, and they all have a "MIME" column that I would like to remove. Is there a way to do this other than using string manipulation / find and replace?   I have tried setting the column to p{0in}, but the column title still remains. I can say "I feed someone". Am I forced to say "I give someone a drink", or is there a single word for this (as in "I [verb] someone")?  Unfortunately my thesaurus can't really help me.