How safe is it to host sensitive data on repository sites like github, bitbucket, etc.?
How secure would github hosting be for private repositories?
$SL_n(\mathbb R)$ is a subgroup of kernel of $f\in$ Hom$(GL_n(\mathbb R), A)$, $A$ is an abelian group. Try to prove the following proposition.     $SL_n(\mathbb R)$ is a subgroup of kernel of $f\in$ Hom($GL_n(\mathbb R), A)$, where $A$ is an abelian group.   My first attempt is to show that $SL_n(\mathbb R)$ is in form of $ABA^{-1}B^{-1}$, then it's clear that $ABA^{-1}B^{-1}$ is in $ker(f)$. However, there exists an elementary row reduction matrix, i.e. $E_{ij}(m)$ adding m times $j$-th row to $i$-th row. Then $E_{ij}(m)\in SL_n(\mathbb R)$. Now, it is possible that $E_{ij}(m)$ is not in $ker(f)$. Then I try to find any relation between $\mathbb R^{\times}$ and $A$, but, except knowing they are both abelian groups, I cannot figure out what else connects those two group. Could you give me some hints? Is there a way to mix LIKE operator with IN ? Something Like  SELECT Id FROM Account WHERE Name LIKE IN:nameList   Where nameList is list of String? Is this is possible ? (I can make a dynamic query by doing OR with all the elements, but was looking for a more elegant way to do this) Math symbol question: Vertical bar for ''evaluated at ...'' Rejecting a PhD offer after having accepted it. Advice? A possible incorrect application of Law of Large numbers How do I kill a process that won't die? I'm unable to kill a process using any of the techniques I'm aware of ("Force Quit" in Activity Monitor, top, killall from the Terminal) and wonder if there are some additional steps I can take.    ~ $ sudo killall -KILL 77439 Password: No matching processes were found ~ $ killall -KILL 77439 No matching processes belonging to you were found ~ $ killall 77439 No matching processes belonging to you were found ~ $ killall Mathematica No matching processes belonging to you were found   FWIW the process is "Mathematica" which I cannot relaunch, Quit, or Force Quit, or sample, either by name or PID, and it appears to have some odd side effects (screenshots don't appear, can't empty trash, and can't even shut down the system).  Are there additional steps that can be taken to really really kill a badly behaved process? Prove if $\operatorname{ord}(a)=m$, $\operatorname{ord}(b)=n$, and $\operatorname{gcd}(m,n)=1$, then $\operatorname{ord}(ab)=mn$.   I was reading this and was thinking how this proof would look like. I tried to do it and am not sure if this is correct. Here is what I did:  If $a$ and $b$ commute then $(ab)^{mn} = a^{mn} * b^{mn} = (a^m)^n * (b^n)^m = 1 * 1 = 1.$ So $ord(ab) | mn$.  Now, take $k = \operatorname{ord}(ab) = m^\prime * n^\prime$ where m' is relatively prime with $n$ and $n'$ is relatively prime with $m$. By the result above $m' | m$ and $n' | n$. Now we have $((ab)^k)^{m/m'} = 1$ since $(ab)^k=1$. But on the other hand, by the commutativity:  $$((ab)^k)^(m/m') =$$  $$((ab)^(m' * n'))^(m/m') =$$  $$ a^{n'm} * b^{n'm} = $$  $$(a^m)^{n'} * b^{n'm'}=$$  $$b^{n'm'} = 1$$  This implies that $n' * m'$ is divisible by $n$. But $m'$ is relatively prime with $n$, so we must have $n' = n.$ By symmetry, $m' = m$. So $ord(ab) = mn$.  Just to say this again, I want to prove if $a$ and $b$ commute and $m$ and $n$ are relatively prime then   $$ord(ab)=mn.$$   The comments are vague. I guess this must be the answer then and there probably is not another way to do this. An Olympiad problem in prime numbers :can we proof that "n" is prime in this case " Let x,n ∈ $\mathbb{N}$  such that :  1+$x^1$+$x^2$+$x^3$+....+$x^{n-1}$ is prime .  Proof that n is prime .  I actually suppose that n isn't prime absurdly so n=p×k such as p is prime ,I also use the $a^n$-$b^n$ formula  and find that $x^k$-1/$x^1$-1 so that means that k=1 and then  n=p which is absurd. Does Anyone has another answer ? Can an Indian travel to India with 50 days before passport expires? My wife is travelling from Philadelphia to India in January 2019 and, on her outbound trip, she will only have 50 days validity left on her passport. However, while in India, she will be renewing her passport. The reply from a similar question seems to answer point 1 below, but I wanted a second opinion to be sure.  Here are the questions we have:  Can she travel from the US to India via Doha, Qatar with passport validity of only 50 days? Can we make a reservation on Qatar Airways for the roundtrip travel using her current passport and before the return from India to the US update passport information on the reservation? With Ubuntu One shut down, is there a way to sync applications between computers? Can the Force be used to fly? How to read a csv file and use the values as x and y points in blender? literally as a hyperbole Possible Duplicate:          I have seen a lot of backlash in internet media against people using the word literally to mean something not literal. Something like "he was literally as big as a house" to mean someone was very big I think this comic sums up the anti literal movement well   Is this actually grammatically incorrect or can the word "literally" be a hyperbole strengthening a metaphor? Commutator subgroup and cyclic normal subgroup Refereeing papers on behalf of a professor: should it be listed on a CV? My professor sometimes asks me to referee papers for him.  Should I list the corresponding journals in the professionals activity section of my CV? Refer to Sheet with value in Cell? The usual way to reference a sheet is  but how do you reference a sheet when the sheet's name is a value in a cell?  For example,   A1 = "Sheet number two" B1 = A1&amp;"!B4"   Here I want B1 to display the value in 'Sheet number two'!B4 but it's not working for me.  Any ideas? How do I find out which DOM element has the focus? I would like to find out, in JavaScript, which element currently has focus. I've been looking through the DOM and haven't found what I need, yet. Is there a way to do this, and how?  The reason I was looking for this:  I'm trying to make keys like the arrows and enter navigate through a table of input elements. Tab works now, but enter, and arrows do not by default it seems. I've got the key handling part set up but now I need to figure out how to move the focus over in the event handling functions. Where did the practice of using apostrophes for possessive nouns but not pronouns originate? Where did the practice of using apostrophes for possessive nouns but not pronouns originate?  For example, possessive nouns (both proper and common) are written with a apostrophe before the final s:        Bill’s, not Bills   Sarah’s, not Sarahs   the bear’s, not the bears   the lizard’s, not the lizards      On the other hand, several possessive pronouns do not have apostrophes before the s:        his, not hi’s   hers, not her’s   its, not it’s   theirs, not their’s   ours, not our’s   yours, not your’s      When and where did this usage originate? Was there any technical advantage of this usage? Where to start with the Star Wars books? bash profile works for user but not sudo