Mathematics

Associated with Math.SE; for both general discussion & math qu...
Jul 9 06:55
similarly. I am now retired, but still dealing with some administrative issues. I hope your new hip does not fight back.
Jul 9 06:50
@copper.hat hello. How are things?
Jul 9 03:00
@skullpatrol Thanks!
Jul 7 23:31
@DanielSank $A-x$ is constant in $y$, so yes.
May 20 19:54
@XanderHenderson I have the left box. I could never take the lies from the right box.
May 20 19:53
@XanderHenderson skeptical does not seem to be in the Crayola colors.
May 20 07:33
Yeah, I've been busy at work. I'm retiring soon, so things have been a bit hectic.
May 20 07:14
Sorry, I am on a Zoom meeting, so I may be a bit slow.
May 20 07:13
@SineoftheTime How are you?
Apr 6 11:08
@onepotatotwopotato shhh! People are sleeping here!
3
Feb 15 22:09
@Thorgott Arrow envy?
Feb 8 20:52
it's raining or it isn't.
Feb 7 23:06
Suppose neither has a subsequence converging to $0$
Feb 7 22:49
that is sufficient, but not necessary.
Feb 7 22:48
@ILikeMathematics Have you checked if the derivative is bounded?
Feb 7 22:43
@skullpatrol Dealing with a lot of stuff irl, but I hope I can spend more time online soon.
Feb 7 22:41
@skullpatrol hey, there. How are you doing?
Jan 10 22:39
The wind...
Jan 10 22:37
@leslietownes You require too much!
Jan 10 22:36
@XanderHenderson We are very thankful. That keeps the fire away from us.
Jan 10 22:36
The town of Topanga has suffered some, but some places have escaped. The southern part of Topanga Canyon is pretty crispy.
Jan 10 22:34
@handan_toddler Thanks. We are, for the time being, safe. We can see flames and see smoke, however.
Nov 9, 2024 21:13
This conversation can go on for days.
Nov 9, 2024 21:13
@copper.hat This is why the room description says, "Just ask; don't ask to ask."
Nov 8, 2024 00:41
@leslietownes Thanks. We are doing better, though my wife fell and has hurt her ankle.
Nov 8, 2024 00:39
@think_meaning_builds Thanks, though I have been checking in here several times a day. We've had some medical issues here recently.
Nov 8, 2024 00:38
@ILikeMathematics I can't paste the javascript into the address bar. I need to have it as a link on the shortcut bar. I don't know if Chrome has that. There is a suggestion on the installation page for Android and Chrome.
Nov 6, 2024 23:29
@ILikeMathematics It works for me. What OS and browser are you using?
Sep 8, 2024 23:26
@Jakobian Also the integer closest to $\frac{n!}{e}$ for $n\ge1$.
Aug 26, 2024 07:55
To see a representation of a Riemann Surface for the cube root, see the answer to this question.
Aug 26, 2024 07:36
You ask about the cube root function. There is indeed only one branch cut, for the same reason as the square root or the log. The Riemann Surface for cube root would have three sheets, as the one for square root would have two, and the one for log would have infinitely many.
Aug 26, 2024 07:27
It doesn't matter where we put the branch cut, as long as it prevents us from circling the origin, which would be the branch point if we were to create a Riemann surface for these functions.
Aug 26, 2024 07:26
If one travels along the unit circle, the square root function comes back to being negative of what it was one revolution prior. If one travels along the unit circle counterclockwise, the log function comes back to being $2\pi i$ different from what it was one revolution earlier.
Aug 26, 2024 07:26
@LuckyChouhan Since you mentioned branch cuts, which are used to make analytic functions on $\mathbb{C}$, I was assuming that's where we were looking. Yes, branch points are used when looking at Riemann Surfaces, which are a bit more complicated than branch cuts. Branch cuts are used when a function would be multi-valued on all of $\mathbb{C}$, such as square root or log.
Aug 26, 2024 04:46
@LuckyChouhan I have seen singular points and branch cuts, but not branch points.
Aug 25, 2024 17:26
@SineoftheTime Ah, I see you noted this.
Aug 25, 2024 17:25
@SineoftheTime it probably has to do with the bounties offered.
Aug 25, 2024 17:01
@Jakobian Belated birthday wishes, etc are a common sentiment in greeting cards here.
Aug 25, 2024 16:47
@Sahaj hello, belatedly.
Aug 25, 2024 15:16
@Pizza I fixed it
Aug 25, 2024 15:14
I hop in once in a while, but things have been slow. I’ve been occupied IRL for quite a while. Now we’re in Mammoth Lakes on vacation.
Aug 25, 2024 15:11
@Pizza $-\frac12$
Aug 2, 2024 08:06
@Sahaj did you get a closed form? I can show how to get it.
Jul 31, 2024 23:15
@leslietownes Dreamer
Jul 28, 2024 14:01
Ack, I will look later, but I think this doesn't work.
Jul 28, 2024 13:52
Look at it as $\frac1{i\sqrt3}\left(\frac1{n-\frac{-1+i\sqrt{3}}2}+\frac1{-n+\frac{-1-i\sqrt{3}}2}\right)$
Jul 28, 2024 13:48
I think this might bear something. I'm looking.
Jul 28, 2024 13:46
$\frac1{i\sqrt3}\left(\frac1{n-\frac{-1+i\sqrt{3}}2}-\frac1{n-\frac{-1-i\sqrt{3}}2}\right)$
Jul 28, 2024 13:40
I don't see a contour that would work.
Jul 28, 2024 13:39
Note that in this sum, $n=0$ cancels $n=-1$, $n=1$ cancels $n=-2$, etc. So the sum is $0$.