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• Today, 03:50
That works. (Nod) Note that $f(x)=\frac{1}{3}(x-2)^2e^{x/3}$ is hard to match with a line, since it has an exponential function in it. However,...
3 replies | 39 view(s)
• Today, 01:06
No one answered to POTW #409. Here is a suggested solution from other: The function S(x)=\sum_{k=1}^{70}\dfrac{k}{x-k} is discontinuous at...
2 replies | 243 view(s)
• Yesterday, 18:07
I appreciate another take on the sites that I have listed. The more views I get from you all, the better. I view the way MHB goes as a group decision...
6 replies | 218 view(s)
• Yesterday, 17:20
Hey mathmari!! We could, but perhaps the intersection points are "nice" points. What are the potentially nice points? (Wondering)
3 replies | 39 view(s)
• Yesterday, 09:27
Yep. (Nod)
4 replies | 74 view(s)
• Yesterday, 02:53
Thank you for pointing this out. I have not looked at other sites in a long time so don't know these things. If a merge was possible I promise I...
6 replies | 218 view(s)
• Yesterday, 02:01
Hey firemath, Thank you for the reply. It's great to hear back from someone on this tough topic. I actually strongly prefer a merge over other...
6 replies | 218 view(s)
• April 7th, 2020, 17:57
When I throw it at Octave online, I get: So it seems it is none of the above, but the answer $3$ is close. For reference, I have re-encoded...
1 replies | 73 view(s)
• April 6th, 2020, 17:02
Prove It is not giving you the answer he is giving you a suggestion that you can use the limit he posted. See if there is any kind of substitution...
6 replies | 108 view(s)
• April 6th, 2020, 12:06
Hi all, I think even we do switch to XF (is still going to happen) the time has come to make a change. We have a database of amazing content here...
6 replies | 218 view(s)
• April 6th, 2020, 11:37
Hi all, I hope you are all safe, healthy, and not affected in a serious way by the world wide COVID-19 virus. Here in the US it has completely...
0 replies | 62 view(s)
• April 6th, 2020, 11:34
Hey mathmari!! This is an example where Newton-Raphson can have problems if we are not careful. If we pick a starting value that is too far from...
4 replies | 74 view(s)
• April 6th, 2020, 10:30
\frac{\left(x\sin\left(\pi\left(x-1\right)\right)\right)}{e^{x/9}(x-1)} The above graph shows that the function repeats its value at $x=1$ when $x$...
4 replies | 74 view(s)
• April 6th, 2020, 10:08
I'm not sure what book you're using or what theorems you my have come across in your studies, so I will quote the two we'll be needing here....
3 replies | 347 view(s)
• April 6th, 2020, 00:28
Hi Alex224, Are you still interested in a solution to this problem? I have something worked out and want to make sure you're still interested...
3 replies | 347 view(s)
• April 5th, 2020, 10:37
I substituted $n=\frac 1{x^2}$, which also means that $x^2=\frac 1 n$. So we get $\Big(1 + \frac 32 x^2\Big)^{1/x^2} = \Big(1 + \frac 32 \cdot \frac... 7 replies | 289 view(s) • April 5th, 2020, 09:14 It's like this: $$\Big(1-\frac 12 x^2 + \ldots\Big)\Big(1+\frac 12 (2x)^2 - \ldots\Big)\\ =1\cdot 1 -\frac 12 x^2 \cdot 1+1\cdot \frac 12 (2x)^2 -... 7 replies | 289 view(s) • April 5th, 2020, 07:04 The series expansion of \cos x = 1 - \frac 12x^2 + \ldots. And the expansion of \frac 1{1-x} = 1+x+x^2+\ldots So:$$\frac{\cos(x)}{\cos(2x)}... 7 replies | 289 view(s) • April 5th, 2020, 01:08 Here is this week's POTW: ----- Suppose that the positive integers$x, y$satisfy$2x^2+x=3y^2+y$. Show that$x-y, 2x+2y+1, 3x+3y+1$are all... 0 replies | 244 view(s) • April 5th, 2020, 01:02 No one answered last week's POTW.(Sadface) Below is a suggested solution: The given function is the square of the distance between a point of the... 1 replies | 187 view(s) • April 4th, 2020, 04:14 This is actually a proof of (ii)$\Rightarrow$(iii) in Lemma 3.2. So we are assuming that (ii) holds. In particular, since$\overline{ f(A) }\$ is...
1 replies | 250 view(s)
• April 3rd, 2020, 22:31
I am reading Aisling McCluskey and Brian McMaster: Undergraduate Topology, Oxford University Press, 2014... ... and am currently focused on Chapter...
1 replies | 250 view(s)
• April 2nd, 2020, 12:25
Klaas van Aarsen replied to a thread f in Calculus
It appears the answer is: dkm Acronym for "don't kill me". Often used when somebody says something that somebody else finds really funny,...
5 replies | 361 view(s)
• April 2nd, 2020, 11:56
topsquark replied to a thread f in Calculus
I believe the proper question is "What the 'f'?" -Dan
5 replies | 361 view(s)
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Was sich überhaupt sagen lässt, lässt sich klar sagen; und wovon man nicht reden kann, darüber muss man schweigen.

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#### April 4th, 2020

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