Notifications or setting for notifications for reputation changes on mobile app Why does the mobile app not notify the user that reputation has changed. For example, if someone has upvoted (or voted down) the question, wouldn't someone like to know? At least it should be a setting in the app that says 'Allow notifications for messages only', or 'Allow notifications' - something like that.  Why does this feature not exist?
Optional Android notifications for reputation changes I would like to get a notification if my reputation count has changed. I think there is already some internal API for that. (I can see that changes in the menu bar in the top).  I'm sure that some people would not like that so that should be optional.
How to prove $\cos\left(\pi\over7\right)-\cos\left({2\pi}\over7\right)+\cos\left({3\pi}\over7\right)=\cos\left({\pi}\over3 \right)$ Is there an easy way to prove the identity?     $$\cos \left ( \frac{\pi}{7} \right ) - \cos \left ( \frac{2\pi}{7} \right ) + \cos \left ( \frac{3\pi}{7} \right ) = \cos \left (\frac{\pi}{3} \right )$$   While solving one , I am stuck, which looks obvious but without any feasible way to approach.   Few observations, not sure if it would help $$ \begin{align} \dfrac{\dfrac{\pi}{7}+\dfrac{3\pi}{7}}{2} &amp;= \dfrac{2\pi}{7}\\\\ \dfrac{\pi}{7} + \dfrac{3\pi}{7} + \dfrac{2\pi}{7} &amp;= \pi - \dfrac{\pi}{7} \end{align} $$ Solve $$u_{xx}-3u_{xt}-4u_{tt}=0$$ where $u(x,0)=x^2$ and $u_t(x,0)=e^x$.  My workings so far: I have factored the differential equation in the following way: $$(\delta_x-4\delta_t)(\delta_x+\delta_t)=0$$ where $\delta_x=\frac{\delta}{\delta x}$ etc. Now if we let $v$ be the solution to $(\delta_x+\delta_t)u$ then we have the following two equations: \begin{eqnarray*} (\delta_x+\delta_t)u=u_x+u_t=v\\ (\delta_x-4\delta_t)v=v_x-4v_t=0 \end{eqnarray*} Now for $v$ we simply find $$v=h(t+4x)$$ where $h$ is an arbitrary function of one variable. Now what remains is find $u$ such that $$u_x+u_t=h(t+4x)$$ I am stuck here, I thought about making a change of variables $\zeta=x+t$ and $\eta=x-t$ and thus using the product rule to show that $u_x=u_{\zeta}+u_{\eta}$ and $u_t=u_{\zeta}-u_{\eta}$ and thus $u_x+u_t=2u_{\zeta}$ and we need to solve $$u_{\zeta}=h(t+4x)$$ (I left out the factor 2 because $h$ is an arbitrary function). Do I simply integrate now and conclude $$u=f(\zeta)h(t+4x)+g(\eta)=f(x+t)h(t+4x)+g(x-t)$$ This seems wrong to me...  Some help would be greatly appreciated! GParted won't let me edit a partition How to output string completions to stdout? Generating all Pythagorean triplets for given Hypotenuse can anybody help me out to find all  Pythagorean triplet when Hypotenuse is given? for example 10 is given i need (10,6,8)  ,and not needed such triplet (10,24,26) as 10 is not Hypotenuse for this triplet! Determinant of block matrix with commuting blocks I know that given a $2N \times 2N$ block matrix with $N \times N$ blocks like   $$\mathbf{S} = \begin{pmatrix} A &amp; B\\  C &amp; D \end{pmatrix}$$  we can calculate $$\det(\mathbf{S})=\det(AD-BD^{-1}CD)$$ and so clearly if $D$ and $C$ commute this reduces to $\det(AD-BC)$, which is a very nice property.   My question is, for a general $nN\times nN$ matrix with $N\times N$ blocks where all of the blocks commute with each other, can we find the determinant in a similar way? That is, by first finding the determinant treating the blocks like scalars and then taking the determinant of the resulting $N\times N$ matrix.  Thanks in advance! rewrite access to collection to avoid "double" finding Calculus function create Create an example of a function $f: \mathbb{R} \to \mathbb{R}$ such that $f(f(f(\mathbb{R}))) = f(f(\mathbb{R})) \neq f(\mathbb{R})$. I want to ask a question about modular arithmetic. I know, that modular multiplicative inverse exists only if modulo and integer are relatively prime. I want to know, are there any ways of division in modular arithmetic, if modulo and integer aren't relatively prime? I tried to find info about that, but failed. Can "zero hours contracts" be considered as not grammatical? Formal writing: "…for my colleagues and {I/me/myself}."? I'm currently using Cambridge English Advanced 1. It's a book that contains past examination papers, and includes numerous samples of authentic writing. This material helps, candidates and teachers, understand what the examiners are ‘testing’ and how these papers are marked. The assessment covers four categories: content, communicative achievement, organisation and language. Each category is awarded a mark between 1 and 5, so the maximum score is 20, and each mark has a brief note attached by the examiner. Any errors of punctuation, orthography, grammar, appropriacy, and vocabulary are left intact. In fact, there are no corrections because the  ‘examiner’ does not specify where the errors lie. This can be frustrating, even though spelling mistakes are rare at the advanced level, and errors in style, collocation or register are still relatively easy to identify, sometimes I'll read a phrase that forces me to ponder.  Dear Director, [ TEXT ] To conclude, this letter is a polite request to cover the costs of a 2 month language course for my colleagues and me. We would be very pleased if the company would do us this favour. Yours sincerely John Smith  The following marks were awarded Content                    5    blah, blah, … Communicative Achievement  2    blah, blah, …     Organisation               3    blah, blah, … Language                   3    blah, blah, …  I am able to pick out six minor errors in that brief extract, maybe some users will identify more, maybe some will identify fewer, and maybe some will say that the language used is perfectly acceptable. But if I can help a candidate attain that elusive B,  I would be delighted. I am interested in (what could be) the 7th error, emphasised in bold. Because the letter of proposal is formal, I feel the phrase, for my colleagues and me, is jarring. I want to change it to for my colleagues and I, but the antecedent requires an object. You would not say: “This is a request to cover the cost […] for I”. So, why use the subject pronoun I in the expression “my colleagues and…”?  Could I use instead, myself?  Which of the following is preferable in a formal written proposal?    …for my colleagues and me …for my colleagues and I …for my colleagues and myself  EDITED: I found a   of the writing sample (11/11) if anyone is interested.  I've looked at the following question,  Some answers appear to be contradictory, the accepted answer says using  I and me are both grammatical, which in my example is not true. Moreover, there's no mention of myself, as a possible solution, in the question. How to get a normal application menu in the top- or titlebar in Gnome Mean Value Theorem: $\frac{2}{\pi}<\frac{\sin x}{x}<1$ For thematic reasons, I am wanting to make a Zatoichi-style character based on using  and Decisive Strike monk alternate feature from the PHB2. The only catch is that Decisive Strike says:     . . . make one attack with an unarmed strike or a special monk weapon . . .   What are all of the official ways to add a weapon to the list of ? I have found only one in the Shou Disciple prestige class (Unapproachable East, p.32), but doing so would mean the earliest the character could use decisive strike with a katana would be level 10. I would like to be doing it no later than level 5 if such an option exists.  Note that, for the purposes of this question, anything that works for "Flurry of Blows" can be interchanged with "Decisive Strike" (e.g. the "Martial Flurry" ability of a Shou Disciple gains ability to use other weapons with "Flurry of Blows," but that is fine). Logging into Ask LibreOffice with my Stack Exchange OpenID If I'm on , I click on OpenID and then enter  and click Log In, I get a page that says:  An error occurred on the server  This event has been recorded.  If you believe you encountered this message in error, please report it.   I clicked report it and here I am reporting it! Using Firefox 26 Chromium on Ubuntu 12.04. Youtube says:     This video is currently unavailable   I don't know why but this is the case for some videos, but not all. Well, most videos. And I don't know what's wrong.  Anyone help? I'm looking for a short story whose title I can't remember.  In it a wealthy man practices cloning and consciousness transfer to achieve immortality, often parading older bodies around his estate naked (not a nice guy). The story follows a final transplant, which doesn't go as expected. The man is left trapped with his memories and no ability to speak, while the clone walks off behaving exactly as he would. How to answer a negative question in English? Q: "Don't you know?"   If I really don't know, how should I respond to this question? Yes or No?  There's a similar question on EL&amp;U, but the answer isn't clear how it works:      Also here on ELU too:      These answers are confusing. I want to know what one word answer I can use. In other words I want to know:   What will native speakers understand if I reply No to this question? What will native speakers understand if I reply Yes to this question? $\frac{1}{A_1A_2}=\frac{1}{A_1A_3}+\frac{1}{A_1A_4}$.Then find the value of $n$ If $A_1A_2A_3.....A_n$ be a regular polygon and $\frac{1}{A_1A_2}=\frac{1}{A_1A_3}+\frac{1}{A_1A_4}$.Then find the value of $n$(number of vertices in the regular polygon).  I know that sides of a regular polygon are equal but i could not relate$A_1A_3$ and $A_1A_4$ with the side length.Can someone assist me in solving this problem? Creating a gradient-based legend I have a map with graduated symbology, with 328 unique values. I would like to add a legend to my map (as in the picture), illustrating that light blue indicates low values and dark blue high values.  I have done this in ArcGIS before. Is there a way to do this in QGIS as well?