What is 10263 process
Why is a suspicious program draining my battery with GPS usage?
This is my first post on this forum :)  I've been trying for a while to solve this problem about symmetric difference of two sets:     Given two sets $A$ and $B$, we call symmetric difference of $A$ and $B$ the following:      $$A\mathrel{\triangle}B = (A\cup B)-(A\cap B)$$      Show that if $A\mathrel{\triangle} B = \emptyset$, then $(A\subset B) \vee (B\subset A)$.   I don’t know where to start; thank you very much for the help :) I want to install Skype, but I can't locate it in Software Center or by using Synaptic Package Manager. Can anyone help me? Can someone help me elucidate the definition of "income" from a tax perspective? More specifically, if Joe is paid for his work in avocados instead of dollars, then would Joe be exempt from paying any income tax for the year? Or would the value of avocados earned for the year be translated into dollars which would then be considered Joe's annual income? If so, what guidelines would one use to make this translation? (Make the assumption that Joe does not sell the avocados (for dollars) at a later date and either eats them or trades them for other real property)  What if he was paid in gold instead of avocados? I'm planning to use USB port for an application(from a device to a PC) but the distance between the device and the PC will be around 15m. The recommended maximum USB cable length is 5m.  How can I buffer the data without loosing any information, safely? Would a USB hub work? I am curious about whether $|x|^p$ with $0&lt;p&lt;1$ satisfy $|x+y|^p\leq|x|^p+|y|^p$ for $x,y\in\mathbb{R}$.   So far my trials show that this seems to be right... So can anybody confirm whether this is right or wrong and give a proof or counterexample? Proving that either $2^n-1 $ or $ 2^n+1$ is not prime Let $A,B$ be real symmetric matrices, and for any $n\in \Bbb N^{+}$, and for all $x,y\in \Bbb R$, we have $$tr(xA+yB)^n=x^ntr(A^n)+y^ntr(B^n).$$  Show that $AB=0$.  My try:since $$(xA+yB)^n=x^nA^n+\binom{n}{1}x^{n-1}A^{n-1}yB+\cdots+\binom{n}{n-1}xA(yB)^{n-1}+y^nB^n$$ so $$tr\left(x^nA^n+\binom{n}{1}x^{n-1}A^{n-1}yB+\cdots+\binom{n}{n-1}xA(yB)^{n-1}+y^nB^n\right)=x^ntr(A^n)+y^ntr(B^n)$$  then  $$tr\left(\binom{n}{1}x^{n-1}A^{n-1}yB+\cdots+\binom{n}{n-1}xA(yB)^{n-1}\right)=0$$ so $$\binom{n}{1}x^{n-1}ytr(A^{n-1}B)+\cdots+\binom{n}{n-1}xy^{n-1}tr(AB^{n-1})=0$$ then I can't  I found this is a nice result, maybe this is an odd problem, and I can't solve it. Thank you. Enable USB debugging (under settings/applications/development) programmatically from within an app I have the following file:  abcde kwakwa &lt;0x1A&gt; line3 linllll   Where &lt;0x1A&gt; represents a byte with the hex value of 0x1A. When attempting to read this file in Python as:  for line in open('t.txt'):     print line,   It only reads the first two lines, and exits the loop.  The solution seems to be to open the file in binary (or universal newline mode) - 'rb' or 'rU'. Can you explain this behavior ? How do I check an iOS device's battery health? Polar form to cartesian Let $\Gamma$ be a circle that passes through the origin. Show that we can find real numbers $s$ and $t$ such that $\Gamma$ is the graph of $r = 2s \cos (\theta + t).$  I know this has to be converted to a cartesian equation, but how do I do this, and what do I do after?  Thanks Proving that $f(x)$ is less than or equal to $1+\pi/4$ Suppose $f$ is a real valued differentiable function defined on $[1,\infty)$ with $f(1)=1$. Suppose also that $f$ satisfies $$f'(x)=\frac{1}{x^2+f^2(x)}.$$ The question is to prove that $f(x) \leq 1+\pi/4$ for every $x \geq 1$    I tried to solve the differential equation but could not bring it in some known form. I examined the derivative of $\tan^{-1}x$ which looks similar to that  in the question. However I could not get any idea with that. Any help shall be highly appreciated. Thanks. Split file into multiple files based on pattern I have a large file that's a couple hundred lines long. This file is partitioned into many parts by a specific identifier, lets say 'ABC'. This line 'ABC' appears 6 times so I want 6 output files. I'm familiar with split and awk but can't seem to create a command line that will do what I've described, any ideas?  Here's an example  ABC line 1 line 2 line 3 ABC line 1 line 2 ABC line1   I'd like three files where ABC is the first line in the new file and it ends before the next ABC is encountered. Zariski Tangent Space and $k[\varepsilon]/\varepsilon^2$ Let $X$ be a scheme over a field $k$, and let $x\in X$ be a rational point, that is, we have $k(x):=\mathcal{O}_x/\mathfrak{m}_x\cong k$.  Let $\alpha:\mathfrak{m}_x/\mathfrak{m}_x^2\rightarrow k$ be an element of $T_x=(\mathfrak{m}_x/\mathfrak{m}_x^2)^*$, the Zariski tangent space to $X$ at $x$.  Using $x$ and $\alpha$, I'd like to define a $k$-morphism of schemes Spec $k[\varepsilon]/\varepsilon^2\rightarrow X$.  In the course of the construction, I need to define a local map of local rings $\mathcal{O}_x\rightarrow k[\varepsilon]/\varepsilon^2$.  Using $\alpha$, what is a natural way to define such a map?  It might be helpful to note that I have an injection $k\hookrightarrow\mathcal{O}_x$ arising from the $k$-scheme structure on $X$.  I think this leads to a decomposition $\mathcal{O}_x/\mathfrak{m}_x^2=k\oplus(\mathfrak{m}_x/\mathfrak{m}_x^2)$ as $k$ vector spaces, from which the desired map would follow, but I can't seem to explicitly see what this decomposition is inside of $\mathcal{O}_x/\mathfrak{m}_x^2$.  This is part of exercise II.2.8 in Hartshorne. How can I get the size of an Amazon S3 bucket? Find all polynomials $P$ such that $P(x^2+1)=P(x)^2+1$ Find all polynomials $P$ such that   $$P(x^2+1)=P(x)^2+1$$ How is light emitted by an incandescent lamp Someone wants to send me cash by DHL. How's this scam supposed to work? This raises a bunch of red flags (also confirmed by googling the email address it came from), but I don't quite understand how this scam is actually supposed to work. So, here it goes:   I put up an ad (for a guitar, 90€) on LeBonCoin (the French equivalent of Craigslist). Someone contacts me by text message (anonymous with no actual phone number), saying they want to continue by email. I then get an email, with roughly the following content (rough translation):     OK, I will buy it, but I need to send you cash by "express DHL letter". The DHL driver will pick up the item when he gives you the cash. I need the following information: full name, postal address, price of the item, and your phone number.    I'm guessing that this works by them requesting some "delivery fee" in advance, but does anyone know how this actually works? Should I write "X and I", "X and me", "I and X", or "me and X" in a conjoined object? Why is carbon dating limit only 40,000 years?