How to number each equation of simultaneous equations grouped by a left curly brace?
Separate labels in cases
Command to move a file to Trash via Terminal How to compute prediction bands for non-linear regression? How do I make Git use the editor of my choice for commits? Prove that $Au\cdot v = u\cdot A^Tv$ Let A be an $n$ x $n$ matrix and let $u$,$v$ $\in$ $\mathbb{R^n}$. Prove that $$Au\cdot v = u\cdot A^Tv$$  I tried using the fact that $A^Tu=A\cdot u$. However, I cannot seem to get to this result. Could anyone please help me out? Difference between wouldn't and didn't What is the difference between would not and did not?  For example:     I called my girlfriend but she wouldn't stop.   I called my girlfriend but she didn't stop. Add new user and add meta at once Multiple Damage Resistance Similar questions to this have been asked, but I wasn't able to find one that answers this specifically.  Say that you have resistance to slashing damage as well as resistance to fire damage (no caveats to nonmagical damage or not).  You are fighting someone who has a flaming greataxe (just an enchanted item) that deals 1d12+STR slashing damage, plus 1d6 fire damage on hit and they hit you.    How do you calculate the damage?   (1d12+1d6+STR)/2 (1d12/2) + (1d6/2) + STR (1d12+STR/2) + (1d6/2) something else? I have a Git repo that I have deleted four files from using rm (not git rm), and my Git status looks like this:  #    deleted:    file1.txt #    deleted:    file2.txt #    deleted:    file3.txt #    deleted:    file4.txt   How do I remove these files from Git without having to manually go through and add each file like this:  git rm file1 file2 file3 file4   Ideally, I'm looking for something that works in the same way that git add . does, if that's possible. Cannot remove a repository that complains it has no public key I marinated chicken five days ago in lemon juice, seasoned salt, and garlic powder, is it still safe to cook in the oven? Debugging automatic properties How do I preview tag wiki exerpt? How do I put a link there? I've edited  to include a link into exerpt. But it shows Markdown source of the link instead of actual link.   How do I preview the exerpt while editing it? Where to find syntax and available Markdown features in exerpts? How do I include the link properly? How to connect Android with MySQL using Mysql JDBC driver Laptop w/o battery US bound flight? According to some reports, your electronic devices are checked whether they turn on before you can get on a US bound flight. What if I carry around a laptop without a battery? Let $x, y$ and $z$ be real numbers such that $x^2+ y^2+ z^2= 1$. Find the   maximum and minimum values of $2x + 3y + z$ .       How can I able to solve the problem? Thanks for your help. Comparing two Lists and returning the distinct values and the differences close votes vs votes remaining I am new to the review part of Stack Overflow and I am trying to understand what is the meaning of votes remaining in the Review | Close Vote.  For example: Today I was at my 39 vote and it said that there was still 21 votes remaining.        However, after my 40 vote:        So, apparently I have started with 60 votes but I can use only 40? I know that the emergency services can be called FREE in the UK by dialing 999 and in the US by dialing 911.   What I don't know is the number to call in other countries and if there is a cost involved. This is something I think most people should find out before travelling but many don't (including me). Hopefully this will help me and other people. I have question about ArcGIS and python script. There are following sample code, So I would like to change Another Field , not OIDFieldName. Please let me know how to change Another Field.  import arcpy import itertools  arcpy.env.workspace = r"C:\path\to\workspace"  base_shapefile = "some_shapefile.shp"  oid_field = arcpy.Describe(base_shapefile).OIDFieldName feature_count = int(arcpy.GetCount_management(base_shapefile).getOutput(0))  for (i, j) in itertools.combinations(range(feature_count), 2):     arcpy.Select_analysis(base_shapefile , "combination_%i_%i.shp" % (i, j), '"%s" in (%i, %i)' % (oid_field, i, j))   These sample code is combination for 5C2. I want to create all combiantions 5C3 , 5C4 , 5C5. Stack Exchange doesn't know when I last checked my global inbox? I am subscribed to get my unread inbox items every 3 hours. It's working well, but today I noticed something quite weird:    For sake of future search, adding the text:  The following item was added to your Stack Exchange global inbox since you last checked it on 2015-05-18  But that's just not true, I checked my inbox yesterday. Not 7 months ago. Can it be fixed, or did I miss something? Even going to my  did not &quot;fix&quot; this, got today another email with the same date as yesterday.