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

Feb2313 09:24 AM
micromass

1 
30,485 
Hi all,
I've been reading up on ways of factorising numbers through the congruence of squares method...

Oct310 12:15 PM
Mathmos6

1 
1,875 
I know that this isn’t very practical but I discovered the following curious inequality when I was playing around with...

Feb1904 10:52 AM
matt grime

1 
1,214 
.

Mar1204 04:05 AM
matt grime

3 
1,771 
I don't know if this identity has been found before but I have never seen it before in my study of Merten's function,...

Jun1904 05:11 AM
Muzza

2 
1,474 
If a connected graph has a Euler circuit then this implies that all the vertices of the graph have even degree. Is the...

Sep1704 09:46 AM
mathwonk

2 
3,218 
how do you prove the distributive quality of the cross and dot products?
thanks very much!

Mar913 04:37 AM
mathnerd15

15 
1,398 
\oint_{0}^{x} dV=i, \oint_{0}^{y} dV=j, \oint_{0}^{z} dV=k
also I want to express in terms of Dirac delta...

Nov313 02:08 AM
mathnerd15

0 
495 
How would one normally solve this type of equation
x^a = b (mod n)
Is there any trick to solve it if I know that...

Sep2311 02:15 AM
Xitami

3 
2,367 
I am looking to find a vector which does not lie in various subspaces.
For example, if I have:
S1 = (xy plane)...

Feb1511 09:40 AM
mathomatt

2 
624 
If G is a permutation group acting on a finite set A and x \inA, then
G = \Delta(x) Gx
where \Delta(x)...

Nov110 07:17 AM
mathplease

4 
1,592 
I'm trying to find the basis for a particular matrix and I get a 3 eigenvalues with two of them being identical to...

Nov904 11:11 AM
matt grime

1 
6,756 
Hi, I'm given a matrix and I need to write it in equation form so that I will have three equations, using x(t), y(t),...

Nov904 12:49 PM
HallsofIvy

1 
4,155 
hello , I don't understand the meaning of the next definition , so , I hope that you can make it easy to understand it...

Oct912 08:12 PM
Stephen Tashi

1 
602 
hello, the theorem says :
let V be a vector space over the field K , let { v1 , v2 , ... , vm } be a basis of V over...

Oct1812 11:39 PM
mathwonk

2 
818 
hi , this proposition is from artin's book ,
it says :
Proposition : suppose an associative law of composition is...

Oct2312 10:30 AM
Maths Lover

2 
779 
hi ,
I met lot's of binary operation which is associative and commtative and I also met lot's of binary operation...

Nov1912 07:10 AM
Dead Boss

5 
1,057 
if A is a tridiagonal Matrix , what does this mean ?
what does tridiagonal mean in matrix ?
what is the property...

Nov2212 11:40 AM
HallsofIvy

2 
852 
hi
if F is inner automorphism , what does this mean ?
I think that if
F : G to G
then
we can write F(x) as ...

Dec1612 04:55 PM
Maths Lover

2 
758 
Theorem :
if S ={ v1 , .... , vn} spans the V.Space V
, L={w1 , .... , wm} is set of linear independent vectors...

Jan113 07:55 PM
mathwonk

10 
1,384 
hi ,
this result is from text , Abstract Algebra by Dummit and foote .
page 120
the result says , if G is a...

Jan2913 01:16 PM
Maths Lover

6 
783 
Please ,
Help me I need informations about compact right topological semigroup
RESERCHES , OR ANY PAPERS...

Apr2709 01:14 PM
maths2009

0 
905 
I read this in a book (it was stats and about poisson approx to normal)
Given was this:
n(n1)(n2) \cdots (nr+1)...

Nov2309 10:42 AM
hamster143

2 
4,717 
Let's say I have a matrix M such that for vectors R and r in xycoordinate system:
R=Mr
Suppose we diagonalized it...

Jul2413 12:19 PM
mathsciguy

2 
402 
Hi everyone.
Long time lurker first time poster.
I am taking a linear algebra class this semester and I am really...

Feb2714 10:03 PM
mathwonk

5 
619 
x1 1 1 0 0
x2 0 0 1 1
x3 = 1 + 1 + 0 + ...

Apr1114 07:37 AM
HallsofIvy

2 
272 
rank(A+B)>=min{rank(A),rank(B)},which holds for allA,B in positive semidefinite matrix

Apr309 09:01 PM
mathsgao

0 
996 
guys,
From the solutions of the Pell's equation x*x2*y*y=1,
how can we prove that whenever y ends in digit 5,...

Sep2107 11:53 AM
ramsey2879

6 
1,967 
How can we proceed to prove the following identity ?

Dec907 09:31 PM
Rogerio

1 
1,411 
Please help me in solving the problem,
find the sum
Sum{r=2 to infinity} (von Mangoldt(r)1)/r
...

Aug1608 09:10 PM
mathslover

9 
3,411 
Hi,
I recall being told in an algebra course in college that there exist groups with matching order tables and that...

Nov3007 08:50 PM
MathsManiac

5 
2,108 
I posted this question but I am not getting anywhere with this question, any help would be very appreciated:
1. let...

Nov508 01:34 AM
robert Ihnot

3 
2,411 
Let n be a nonzero integer. An abelian group A is called ndivisible if for every x \in A, there exists y \in A such...

Dec1508 12:15 AM
adriank

13 
1,508 
Let p be a prime, G a finite group, and P a pSylow subgroup of G. Let M be any subgroup of G which contains N_G(P). ...

Dec808 09:35 PM
mathwonk

1 
1,265 
Let M be the \mathbb{Z}module generated by the elements v_1, v_2 such that (1+i)v_1+(2i)v_2=0 and 3v_1+5iv_2=0. Find...

Dec808 11:38 PM
adriank

1 
1,171 
Suppose is a commutative diagram of Rmodules and Rmodule homomorphisms.
(a) Suppose that \phi is injective. Prove...

Dec808 09:40 PM
mathsss2

0 
1,555 
Let K be a field, \nu : K^* \rightarrow \texbb{Z} a discrete valuation on K, and R=\{x \in K^* : \nu(x) \geq 0 \} \cup...

Dec908 02:58 PM
mathwonk

1 
1,221 
Identify all the subfields of a field F=F_{p^{18}}, with p^{18} elements where p is a prime. Draw the lattice of all...

Dec908 11:43 PM
adriank

2 
2,126 
K=\mathbb{Q}(\sqrt{2+\sqrt{2}}) is a Galois extension of \mathbb{Q} . Determine \text{Gal}(K/\mathbb{Q}) and describe...

Dec1008 08:46 PM
Office_Shredder

1 
1,794 
The parts of this problem form a proof of the fact that if G is a finite subgroup of F^*, where F is a field (even if...

Dec1408 06:28 AM
rscosa

1 
1,701 
I don't understand this proof, specifically the part in red, I don't understand. Please help me understand this step...

Jan609 08:44 PM
mathsss2

2 
1,125 