aligning equations in latex problem
Best way to create an system of equations environment?
error when adding user to wheel group in CentOS 7 I am trying to grant sudo privileges to a user of a CentOS 7 devbox by typing gpasswd -a user wheel, but the attempt is failing.  What am I doing wrong?    Here is what I typed:    I discovered that the user is not in the wheel group as follows:    [user@localhost git]$ sudo yum install git [sudo] password for user:  Sorry, try again. [sudo] password for user:  Sorry, try again. [sudo] password for user:  user is not in the sudoers file.  This incident will be reported.   I then logged in as root and typed the following to add the user to the wheel group:    [user@localhost git]$ su - Password:  Last login: Thu Aug 20 17:11:31 PDT 2015 on pts/0 [root@localhost ~]# gpasswd -a user wheel Adding user user to group wheel [root@localhost ~]# exit logout   I finally tried to use the sudo command again but it failed as follows:    [user@localhost git]$ sudo yum install git [sudo] password for user:  user is not in the sudoers file.  This incident will be reported. [user@localhost git]$ Avoid trailing zeroes in printf() I keep stumbling on the format specifiers for the printf() family of functions.  What I want is to be able to print a double (or float) with a maximum given number of digits after the decimal point.  If I use:  printf("%1.3f", 359.01335); printf("%1.3f", 359.00999);   I get  359.013 359.010   Instead of the desired  359.013 359.01   Can anybody help me? How can I resize (not compress) multiple images in a MS Word document? In a blank document, I insert images (screenshots - all are of same size and same format) from a folder. I want to resize the images to a desired size. All now I am doing is selecting one image by one, setting its size. Word does not seem to have multiselect working for images.  Ideally, I want to select multiple images set its size in one go with out use of a macro. How can I repair a buried 120v cable splice to make it meet code? I have an electrical question. I have a cable feeding an outdoor yard light. It was cut, I spliced it, soldered it and wrapped it with tape. Is there a way to splice and bury it safely to code? If not, I'll need to dig a 30 foot trench to replace the whole length.  Was about 8 inches below ground, surfaced over the years and probably hit with the weed trimmer.   It is outdoor cable inside copper tubing. Years ago when I bought the wire I knew outdoor was gray. The box said outdoor but it is white like indoor wire.   It was spliced about 20 years ago but am fixing up house and like to hide the ugly splice. I would like to increase the size of pretty much every headlines, so that it is more prominent than the normal text.  I read about the  package, but can't seem to find good example how to use the package.  Using Gonzalo Medina does in fact change the font size, however, it changes the default font as well.  Before:    After: Clean install of Windows 10 OEM: license key issues? Does the series $\sum \sin^{(n)}(1)$ converge, where $\sin^{(n)}$ denotes the $n$-fold composition of $\sin$? In my project, I use a lot of geodata from different directories. Now I want to give the QGIS project to a colleague (eg on a CD).  Is it possible to copy the shapes from different directories automatically to one directory? Is voltage the speed of electrons? I tried to log into Minecraft today to find that my password isn't working. I tried to change it, but I can't login to my email because I forgot the answer to my security question. I tried changing the email to a different one, but that didn't work for some reason (it kept saying "invalid email"). I don't have my transation ID because I forgot which credit card I used.  Does this mean that I have to buy a new Minecraft account? I am currently developing a website which is going to take some time to finish. I need to move some 'stuff' to production frequently, while maintaining a under construction status. My front page will clearly mention that my website is under construction.  I know crawlers will access my URL before I am ready to go live. Should I tell them my site is under construction (no need to index)? If yes how?  P.S.: Eventually, I am ok to let them see my under construction front page. Can you be sued for using publicly used images on a blog without copyright permission? Evaluating the infinite product $\prod\limits_{k=2}^\infty \left ( 1-\frac1{k^2}\right)$ Evaluate the infinite product $$\lim_{ n\rightarrow\infty }\prod_{k=2}^{n}\left ( 1-\frac{1}{k^2} \right ).$$  I can't see anything in this limit , so help me please. Emmy Noether's theorem in simpler terms I'd like to understand  and its contents as to what it implies in a bit simpler terms. I am familiar with mathematics unto Calculus 1,2,3 and some linear algebra and group theory. I am familiar with that for each symmetry there is a conservation law.    Now is there a one-one correspondence between these two always? What about laws like conservation of charge?  And conservation of energy?  And conservation of mass?  Considering our view of nature was changed as Special Relativity was introduced and thus, what earlier the theorem would have asserted as mass and energy to be originating from different symmetries then how did we reconcile these two as just one symmetry? Set active image node with python There's any way to change it directly by Python, or there's any way to set by Python what node image is the active to display in viewport (Textured) and bake? I have a folder on my desktop which is named ".." (which itself contains subfolders with an empty name). The folder can't be deleted the usual ways, even not when using the CLI. Does anyone know how I can remove this folder on Windows Vista 64-bit?  Renaming does not work, either (obviously).  This is what "dir /x" echoes:  09.10.2009  15:04    &lt;DIR&gt;                       . 09.10.2009  15:04    &lt;DIR&gt;                       .. 08.03.2007  11:18    &lt;DIR&gt;                       cgi-bin                0 Datei(en),              0 Bytes                3 Verzeichnis(se), 45.866.037.248 Bytes frei How do I align the viewport to a face normal? I would like to align the view straight on to a face, perpendicular to the normal. How do I align the 3D viewport to the face of a mesh? Etiquette for revision comments How to see python symbolic names of objects on cursor hover of menu items in Blender 2.8 in Blender 2.79 one could hover over a UI element and see the symbolic python name of said element. How would one accomplish the same with Blender >= 2.8? What do I need in a camera to take non-blurry photos of a fast-moving child?