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

Feb2313 09:24 AM
micromass

1 
35,127 
I'm trying to understand the category theoretic proof of free groups.
I know a bit of group theory but little...

Mar2014 04:44 AM
James MC

0 
469 
Am i correct if I say that Fiedler number surges when percolation is at percolation threshold? Assume a randomly...

Mar813 10:44 AM
kosmos

0 
470 
Dear All:
For a line structure(say a very long atomic chain) and a closed loop structure( connect the head and tail...

Oct3113 10:59 PM
peter308

0 
470 
I imagine a matrix group, with multiplication as the composition rule, to always possess the quality of having centre...

Feb2014 01:57 PM
pasmith

3 
470 
How I do for calculate the solid angle formed by 3 vectors like:
http://s30.postimg.org/61lpvmi4h/solid.jpg
?

Feb1814 11:15 AM
Jhenrique

2 
471 
Hi Guys,
I have just started studying about this field.
Can you give me some ideas about some best eigen value...

Jun2213 08:50 PM
lurflurf

1 
473 
Hi everyone,
I have a square matrix J \in \mathbb{C}^{2n \times 2n}...

Feb2714 11:57 AM
Sam1984

0 
473 
okay so i'm having some conceptual difficulty
given some vector space V (assume finite dimension if needed)
...

Apr914 08:07 AM
HallsofIvy

6 
475 
Is it? Personally, I think it is since the max power on any unknown is 1, no trig function, no product of unknowns...

Oct1212 02:20 PM
Studiot

1 
476 
Is there an expression, in general, for the product of two matrix exponentials, for noncommuting matrices?
i.e....

Apr114 12:36 PM
micromass

1 
477 
Given the following: $$\\ \begin{bmatrix}
A & 0\\
0 & B\\
\end{bmatrix}$$ the eigenvalues is exactaly A and B. So...

May2014 08:43 PM
Matterwave

5 
477 
Hi, all:
Say we have a barebones Vector Space v, i.e., V has only the basic vector space
layout; no...

Apr2711 04:47 PM
micromass

1 
478 
Hi there.
I would like to learn more, if any, on interesting applications of Euclidean rings both in mathematics,...

Jun2313 04:33 PM
jamesb1

0 
478 
If the group G/ is abelian then how do we show that xyx^{1}y^{1}=1?
Thanx

May2614 03:09 AM
homeomorphic

3 
478 
If I have two square nonnegative primitive matrices where the PerronFrobenius Theorem applies how would I calculate...

Jul413 09:01 PM
Simon Bridge

2 
480 
I have been trying to implement this Wave equation into java:
A = amplitude of wave
L = wave length
w...

Feb314 06:09 AM
pasmith

1 
480 
I'd like to figure out why
f(x) = x^n  r e^{i \theta} = \prod_{j = 0}^{n  1} ( x  r^{1/n} e^{i \theta / n} e^{2...

Feb914 03:33 PM
AlephZero

2 
480 
I am trying to understand Galois Theory and reading through various theorems and lemmas, some of which are still...

May1414 10:52 PM
Boorglar

2 
480 
If I have (α1,β1,γ1) and (α2,β2,γ2) as two set of rotation angles in radians.Where α is Yaw of α about z axis, β is...

May1514 07:09 PM
abubakr

4 
480 
The two properties every linear transformation T: V > W has to satisfy is
T(u + v) = T(u) + T(v), for u,v in V (i)...

Feb1714 04:01 PM
jgens

4 
482 
Hi, All:
I have seen Orthogonal groups defined in relation to a pair (V,q) , where V is
a vector space , and q...

Jun1011 09:11 PM
Bacle

0 
483 
Here it is for those interested.
http://arxiv.org/pdf/1305.2897.pdf

May2813 08:47 AM
epsi00

0 
483 
I am reading Dummit and Foote Ch 15, Commutative Rings and Algebraic Geometry. In Section 15.1 Noetherian Rings and...

Oct3013 11:54 PM
Math Amateur

2 
483 
There are lots of examples of numbers where "is it a rational number" has been an open question for a while before...

Jun2113 01:54 PM
Office_Shredder

0 
484 
is it true that \frac{1}{g_{ab}}=g^{ba}? I am a bit confused by the index notation. I especially wonder about the...

Apr614 06:12 PM
HallsofIvy

3 
484 
Let L: R3 > R3 be L(x)=
\begin{pmatrix}
x1+x2\\
x1x2\\
3x1+2x2
\end{pmatrix}

May2014 03:11 AM
sudhirking

6 
484 
...
I think I've misunderstood their definition of an invariant. The pth power of the trace function seems to...

Nov2511 04:06 AM
Rasalhague

0 
485 
Hi,
I have found an encryption algorithm named ECKSPS (published in a paper named 'efficient conjunctive keyword...

Apr1013 03:13 AM
sanderpotter

0 
486 
The Fourier series can be used to represent an arbitrary function within the interval from  π to + π even though...

Jun2813 03:39 PM
tinytim

1 
486 
Is it possible for a variable to exit the basis and after a couple of iterations, enter it again? Are there any...

Jun911 09:31 AM
arthurav

0 
489 
I am reading Dummit and Foote Ch 15, Commutative Rings and Algebraic Geometry. In Section 15.1 Noetherian Rings and...

Oct3013 10:52 PM
Math Amateur

2 
490 
Hello, I was "playing around" with the S_{3} Young Tableaux, and trying to calculate the Young Operators for them......

Dec1313 01:33 PM
ChrisVer

0 
490 
I know it should be absolute zero, but in a scientific calculator, which is an app actually, its value is shown...

Jul2114 05:34 AM
Adit

3 
490 
I'm trying to understand in an applied sense what could a change of basis based on a transformation matrix consisting...

Dec713 09:06 AM
TheOldHag

0 
492 
Hi, let G be any group . Is there a way of embedding G in some other
group H so that G is normal in H, _other_ than...

Apr2514 06:10 PM
micromass

1 
492 
The linear combinations of V = (1,1,0) and W = (0,1,1) fill a plane.
My question is how do i describe that plane?...

May2514 08:28 PM
HallsofIvy

3 
492 
given the scalar product
(Uf  Uf) = (e^{t}f e^{t} f)
with U=exp(tA) for an operator A , what condition...

Apr1711 04:52 AM
zetafunction

0 
493 
Do you know any example of matrix which is not symmetric and has real eigenvalues?

Apr2414 03:20 AM
maajdl

1 
493 
Dear All:
For a line structure(say a very long atomic chain) and a closed loop structure( connect the head and tail...

Nov113 08:30 AM
HallsofIvy

4 
494 
Can someone tell me why Sum from j=1 to 3 of y_j*(x'_j , x'_k) = (f , x_k) for 1<=k<=3
where (x1,x2) is the...

Mar2813 06:18 PM
ericm1234

0 
495 