Canon Pixma iP2820 Driver for Ubuntu?
How can I install a Canon printer or scanner driver?
Show that every group of prime order is cyclic Show that every group of prime order is cyclic.   I was given this problem for homework and I am not sure where to start. I know a solution using Lagrange's theorem, but we have not proven Lagrange's theorem yet, actually our teacher hasn't even mentioned it, so I am guessing there must be another solution. The only thing I could think of was showing that a group of prime order $p$ is isomorphic to $\mathbb{Z}/p\mathbb{Z}$. Would this work?    Any guidance would be appreciated. chrome disable or change keyboard shortcut ctrl+shift+c developer tools console? How can I disable the Keyboard Shortcut ctrl+shift+c in Google Chrome to bring up the Developer Tools console?  I find myself trying to copy+paste content from the browser and mistakenly typing ctrl+shift+c when I really want to do ctrl+c instead.  How can I disable the current keyboard binding or change ctrl+shift+c to do the same as ctrl+c in Google Chrome? Automating the appearance of email addresses as images Publishing pdf manuscripts on the web with emails embedded in the file results in spam.  More generally, I am looking for a way to automate the conversion of a string to an image.  It's quite easy to solve this old problem using  (more ). The trouble is that you need a distinct file and typesetting run, and you end up with unnecessary image files that you cannot delete carelessly lest you also delete non-generated images.  Can you think of a way to do this on the fly? It's understood that people will have to type the email addresses if they need to message you, but that's the point.  More briefly/concretely...  With what can one replace #1  \documentclass{article} \newcommand\showasimage[1]{#1} \begin{document} \showasimage{joe@foo.bar} \end{document}   such that #1 appears as an image?  Edit  It would be really nice if the pdf file remains vectorial. Why don't we include $\rho g h$ in a hydraulic jack below? Consider a hydraulic jack with massless pistons as follows.    The famous equation for this system is   $$ \frac{F_1}{A_1}=\frac{F_2}{A_2} $$  My question is why isn't the equation as follows?  $$ \frac{F_1}{A_1}=\frac{F_2}{A_2} + \rho g h $$  It is based on  my understanding that any points in the same horizontal line have the same pressure.  Could you spot my misconception? Prove $\left| \int_a^b f(t) dt \right| \leq \int_a^b \left| f(t) \right| dt$ I've been given a proof that shows the following:  If $f:[a,b]\to \mathbb C$ is a continuous function and $f(t)=u(t)+iv(t)$ then $$\left| \int_a^b f(t) dt \right| \leq \int_a^b \left| f(t) \right| dt$$ The proof begins by letting $\theta$ be the principle argument of the complex number $\int_a^b f(t)dt$ and there is one step in the proof I don't understand; can anyone explain to me why $$\int_a^b e^{-i\theta}f(t) dt=\Re\bigg(\int_a^be^{-i\theta}f(t)dt\bigg)$$  Would this not imply that the imaginary part of the left hand side is equal to $0$? I'm not sure why the LHS and RHS would be equal here. Question mark or bold citation key instead of citation number Persist sort/filter selections Highest power of a prime $p$ dividing $N!$ How does one find the highest power of a prime $p$ that divides $N!$ and other related products?  Related question: How many zeros are there at the end of $N!$?    This is being done to reduce abstract duplicates. See   and  for more details. How to disable gedit side panel? How do i disable this stupid side panel of gedit, that somehow appeared? There is nothing in the settings or plugins. Tried rm -r -f ~/.config/gedit as well, with no success. I don't have big screen and i find it totally useless and eating up what little free space for editing documents i have. See Screenshot The three files are read in this order?  .bash_profile .profile .bashrc   This is not happening when I first open a terminal.   I have trace statements in the files appending to the file init.log. Please take a look at the following. It begins after opening a terminal. I have placed a comment to show where the log picks up after the su command.  stephen@debian:~$ cat init.log reading .bashrc done reading .bashrc stephen@debian:~$ su - stephen Password:  stephen@debian:~$ cat init.log reading .bashrc done reading .bashrc # # after su # reading .bash_profile reading .profile reading .bashrc done reading .bashrc done reading .profile done reading .bash_profile stephen@debian:~$    So the su - login triggers the expected sequence however the initial login reads only the bashrc. This cannot be correct. Can someone explain under what conditions this would occur. I could modify the bashrc and profile files so that the initial read includes all expected files but I would rather get to the root of the problem and fix it there. Accessing raster attribute table in QGIS? I have some Python code that makes Raster Attribute Tables for GeoTiffs using GDAL.    In ArcGIS I can see these attribute tables fine and they behave how I like (as classifications) but in QGIS the whole concept of an attribute table seems to be missing.    Is there any way to access a RAT in QGIS? I have a custom object. I want to put in a business rule so that a combination of two fields must be unique.   So I have Field1 and Field2 and want the combination to be unique:  Field1=4, Field2=7 Field1=4, Field2=8   is ok  But,   Field1=4, Field2=7 Field1=4, Field2=7   is not ok  What is the easiest / best way to do this? Thanks. passive Vs active or omission of 'which is' What is the part of speech of 'regarded' in the following?     "a quality of beauty and intensity of emotion regarded as characteristic of poems"    Why isn't it "... [which is] regarded ..."?  And in another case:      "a small lizard with wide feet, found especially in warm countries"     And also:      "Words used to describe writing or speech style"    In all these examples, why shouldn't the verbs be in their passive form (e.g. which is found, words that are used)?   I am a ESL learner and I am very confused by these usages! How can I make Ubuntu 18.04 / 18.10 desktop use Unity (be like Ubuntu 14.04)? Any way to send a personal message to another user? There has been quite a few times that I wished I could send a message to another user on SO - not ask a question for everyone to see, but just a short message informing them of something or requesting them to do something.  Are there any plans to allow this to happen in the future?  Related: How to distribute proprietary Mathematica code How to make a traditional division How to make the traditional division? Like that:  a |b_ r  c I have a quaternion, coming from a system with the following:(intertial sensor)  Right handed. Forward direction: Y axis Right direction: X axis Up direction: Z axis   I need to convert this into a coordinate system that is: (Unreal engine)  left-handed. Forward direction: X axis Right direction: Y axis Up direction: Z axis   I have tried negating the axis, and angle, I have tried switching values, i cannot get this to work. All help greatly appreciated! I am working in C#, with Microsoft.Xna.Quaternion. how to loop through arguments in a bash script How to enable assembly bind failure logging (Fusion) in .NET How do I enable assembly bind failure logging (Fusion) in .NET?