
Please post any and all homework or other textbookstyle problems in one of the Homework & Coursework Questions...

Feb2313 09:25 AM
micromass

1 
28,719 
What is the relationship with the Mobius strip (or loop) and the 4 dimension? Is Mobius strip a four dimensional...

T 11:28 AM
Terandol

6 
131 
I find, in KolmogorovFomin's Элементы теории функций и функционального анализа, at the end of § 5 of chapter IV,...

T 10:29 AM
economicsnerd

10 
175 
Edit: I originally wrote that ##\mathcal A## is a Banach algebra. The assumption that goes into the theorem is...

Y 05:46 PM
Fredrik

5 
185 
I would like to prove , as a subset of R with the standard Euclidean topology, is compact. I do not want to use Heine...

Y 04:31 PM
Terandol

1 
90 
Let's say you integrate a complex function along a curve. How do you visualize it? This is explaned very well in...

Sep1214 09:49 AM
bobby2k

0 
95 
If I create a bijective map between the open balls of two metric spaces, does that automatically imply that this map...

Sep1114 05:24 PM
Jorriss

1 
103 
"In a private project of mine, I have come across a challenging problem.
I have 3 points: A, B and C.
A is the...

Sep1114 04:57 PM
AtlasSniperma

2 
166 
Hi, friends! I find an interesting unproven statement in my functional analysis book saying the image of the closed...

Sep1014 08:07 PM
DavideGenoa

2 
156 
Hello
Normally in order to change the order of limit and integration in rimann integration, you need uniform...

Sep1014 04:27 PM
gopher_p

7 
199 
The wikipedia article on \sgn (x) (http://en.wikipedia.org/wiki/Sign_function) states that,
\frac{d}{dx}\vert...

Sep1014 09:40 AM
jostpuur

2 
157 
If I stated a problem that you have to find the solution
to the problem
x(0) = x_0 < R

Sep1014 08:49 AM
jostpuur

0 
83 
hi there,
I am trying to prove the following inequality:
let z\in \mathbb{D} then
\left \frac{z}{\lambda}...

Sep914 03:54 PM
Likemath2014

20 
433 
Dear friends, I read that, if ##A## is a bounded linear operator transforming I think that such a terminology implies...

Sep914 03:25 AM
DavideGenoa

4 
183 
integrate e^z/(1cosz) dz over circle of radius, say 2
i can't seem to recall how it is done.
singularity at z=0...

Sep814 09:48 PM
WWGD

8 
169 
I came across an interesting problem that I have made no progress on.
Let f be an analytic function on the disc ##D...

Sep814 09:14 PM
WWGD

5 
226 
Dear friends, I have been trying in vain for a long time to understand the proof given in Kolmogorov and Fomin's of...

Sep714 04:32 PM
DavideGenoa

10 
205 
Definition of 'Limit of function (f) at x=p'
Let E be domain of f and p be a limit point of E. Let Y be the range...

Sep714 06:39 AM
Fredrik

3 
150 
Before asking a question I would first like to mention the definitions of limit of function and differentiality at x=p...

Sep514 06:22 PM
jwqwerty

8 
217 
I just completed a brief introduction to branch points in complex analysis, and I find it difficult to imagine/come up...

Sep314 05:44 PM
jasonRF

4 
277 
How I can show the following
\int _{\mathbb{T}} \frac{1}{1e^{i\theta}z^2}dm(e^{i\theta})= \frac{1}{1z^2}...

Sep314 03:47 PM
Likemath2014

0 
136 
Hello,
I am facing some problem with Poincare disc.
(1) How to visualize a Poincare disc?
(2) The arc which...

Sep314 12:18 PM
Incnis Mrsi

4 
252 
Dear friends, my book (an Italian language translation of KolmogorovFomin's Элементы теории функций и функционального...

Sep214 07:18 AM
micromass

11 
237 
I read that in any locally convex topological space X, not necessarily a Hausdorff space but with linear operations...

Aug3114 05:09 PM
DavideGenoa

4 
172 
I've taken basic undergraduate Real and Complex Analysis, and I've noticed they focus on different kinds of functions....

Aug3014 09:39 PM
FactChecker

5 
418 
I think I've found a proof where Rudin is actually too wordy! For your welcomed inspection, I will type a part of said...

Aug2914 12:51 AM
WWGD

4 
185 
I have to do a project on the dimension theory buy i cant find any info on it. This is the wikipedia page and if you...

Aug2614 10:00 PM
mathwonk

23 
576 
How to determine the function from its graph if it has a nonsimple shape?
Given a graph (see attachment) where set...

Aug2414 07:32 AM
HallsofIvy

1 
189 
I know this post is in the topology thread of this forum, for group theory, this seemed like the reasonable choice to...

Aug2314 11:21 AM
xAxis

2 
264 
Say we have two functions with the following properties:
f(x) is negative and monotonically approaches zero as x...

Aug2214 10:59 AM
ekkilop

2 
191 
Hi all,
Please help! I am reading the paper "A note on contiguity and Hellinger distance" by J. Oosterhoff and W.R....

Aug2214 12:13 AM
victoriaabc

2 
185 
Hi all, I am trying to construct a continuous matrixvalued function h=h(f,g) ; f,g in C^1,all defined in an open...

Aug1414 10:35 PM
WWGD

4 
559 
Recently I came across this information:
\text{S1} = 1+1+1+1+\dotsb= \frac{1}{2}
\text{S2} = 11+11+\dotsb=...

Aug1314 03:32 PM
mathman

1 
238 
We know that the derivative of the general Schwartz  Christoffel map (function) is:
f'(z) = λ(z ...

Aug1314 11:19 AM
D_Tr

2 
1,416 
Hello. I'm wondering if anyone has a table of transforms showing the result of an Abel transform on a Gaussian...

Aug1114 10:45 AM
Mr Boom

1 
271 
Just as we have orthogonal vectors/vector spaces/etc., we can have orthogonal functions/function spaces/etc. I'm...

Aug1014 09:45 PM
16universes

17 
462 
The Problem
Let x and y be real numbers such that y<x, using the Dedekind cut construction of reals prove that...

Aug914 06:40 PM
loops496

5 
326 
I'm trying to understand Čech cohomology and for this I'm looking at the example of ##S^1## defined as ##/\sim## with...

Aug714 12:05 AM
mathwonk

2 
1,580 
I am trying to reconcile the following statement:
" u<=eps*f means u=O(eps) ("u is order eps")... "...

Aug414 11:58 PM
Simon Bridge

7 
304 
Consider the sets ##X:= \{x\in\mathbb R^2: \enspace x(1,0)_2 \leq 1\}## (a ball) and ##Y:=co\{(0,1), (0,1),...

Aug414 10:34 PM
economicsnerd

2 
208 
Are plane and surface of sphere different metric spaces?
Can distance function of plane be applied as distance...

Aug214 09:00 PM
gianeshwar

6 
348 