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

Feb2313 09:24 AM
micromass

1 
35,179 
Dear Friends & Colleagues,
I have a couple of nagging issues with mathematics I was hoping any one of you would...

Jan1813 10:42 AM
Stephen Tashi

5 
2,330 
My textbook says that...
If M is a left Rmodule, then a submodule N of M...is an additive subgoup N of M closed...

Jan1513 09:33 PM
mathwonk

3 
788 
Hello, I have a simple(or not?) math problem:
I have equations of 3 lines in R3 trought the origin:
line l1:
...

Jan113 08:12 PM
chiro

5 
1,368 
The logic that odd composite with least difference will be factored easily and large difference would factored hardly...

Jan113 09:30 AM
mfb

4 
1,612 
I'm trying to understand the derivation of polynomial regression.
Given data points: . So a 2nd degree curve will...

Jan813 02:58 PM
SteamKing

10 
1,231 
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 
1,527 
Suppose that a = aBc where a and c are vectors and B is some matrix that changes as time "continuously" goes on ...

Dec3112 04:20 AM
dotiozeros

0 
798 
Consider an m x n table containing single digits 0 to 9. So each cell contain the digits 0 to 9.
My goal is to make...

Jan313 11:01 AM
mfb

7 
2,175 
Hello everyone,
I found that you're actively discussing math problems here and thought to share my problem with...

Jan113 03:33 AM
phd_student

0 
981 
Hello everyone!
I'm a 1st grade student in a slovenian high school. Recently, I've became very intrested in numbers...

Jan613 09:22 PM
skiller

11 
2,312 
Hi. Define a linear mapping F: M2>M2 by F(X)=AXXA for a matrix A, and find a basis for the nullspace and the...

Jan213 11:59 PM
nickthegreek

2 
906 
I'm trying to compute the complexity of the quadratic program: $$\displaystyle\min_{\mathbf{X}} (\mathbf{X^TQX +C^TX})...

Jan313 08:41 PM
lavinia

3 
750 
Why do we have xaxis perpendicular to yaxis? Why not 45° or something else?
Even if we keep any other angle other...

Jan513 12:16 PM
Studiot

9 
1,593 
Hello all,
I have a question:
assume in matrix M(n*n), each element M(i,j) of matrix is computed as M(i&)*M(&j) /...

Jan613 01:06 PM
sanaz

4 
981 
I have some technical questions about spans and bases which my textbook really does not cover very well. I would...

Jan613 06:16 PM
AlephZero

2 
908 
I am a bit confused about the page that I attached...
I don't understand part (ii)...
How can you compute XX? So...

Jan613 12:07 AM
Artusartos

6 
822 
Hi
I am going through Sheldon Axler  Linear Algebra Done right. The book States the Complex Spectral Theorem as :...

Jan713 11:38 AM
vish_maths

4 
1,106 
Hey guys, lurked here a bit, but now I'm in this new math course right. So anyway it seems like a completely new...

Jan913 06:59 PM
sniper_spike

4 
838 
I have no idea what this is! Please can someone explain comparing to a 3x3 matrix?

Jan613 05:19 PM
mfb

3 
1,063 
No not the trival solution but generally GCD(x,y) = 1 when GCD(A,B)=1
x =...

Jan713 12:40 AM
ramsey2879

0 
999 
I recently got (re)interested in C* algebras. Poking around, I gathered that there is some way of constructing a C*...

Jan713 12:17 PM
marcus

0 
558 
I have a question about the proof that I attached...
1) Since R/I is not the zero ring, we know that 1 \not= 0....

Jan713 09:01 PM
Number Nine

1 
826 
Hello all,
I am new to this forum but am glad I found it, I have a quick question about condition numbers and order...

Jan1013 06:08 PM
AlephZero

5 
1,206 
I don't know if this is the correct section to post this, but does Galois theory has any applications in physics?

Jan1313 03:47 AM
Jim Kata

2 
1,960 
Hi,
Let the linear system Ax=b.
I am looking for literature describing how changes on coefficients matrix A affect...

Jan813 05:01 PM
yiorgos

0 
613 
I'm unable to understand this generalization of vectors from a quality having a magnitude and direction, to the more...

Jan1413 10:29 AM
danzibr

4 
1,368 
Hi guys, first post!
I'm doing some side work on coupled oscillating systems, and I've almost found a procedure to...

Jan913 03:39 PM
Jack Jenkins

0 
908 
Hello,
I was wondering if this problem is one that is solvable, and if so, if I would be able to solve it in a...

Jan913 11:31 PM
hello95

3 
1,088 
In this video:
http://www.youtube.com/watch?v=FZzQKBlpE
At the time 2:10, I don't understand why we have to...

Jan1413 07:15 AM
Artusartos

4 
1,079 
I was thinking about the following proposition that I think should be true, but I can't pove:
Suppose that F is a...

Jan1613 05:59 AM
lavinia

2 
978 
Hi all,
I have been asked the question by a friend of mine who was working on a computer algorithm where he needed...

Jan1113 03:01 PM
HallsofIvy

4 
1,265 
Pretty much what the title says.
Suppose we have a topological vector space $(X,\tau)$ and $U\subseteq X$ is...

Jan1213 09:32 AM
danzibr

5 
1,256 
Perhaps forum members can advance science by solving this optimization problem from The Protein Engineer ...

Jan1313 04:10 PM
homeomorphic

2 
845 
From my textbook:
A free Rmodule is "A left Rmodule F is called a free left Rmodule if F is isomorphic to a...

Jan2113 02:51 AM
algebrat

1 
1,057 
A Theorem in our textbook says...
If R is a PID, then every finitely generated torision Rmodule M is a direct sum...

Jan1813 03:00 PM
mathwonk

1 
964 
Hi,
For any odd composite 'N', let u = (N1)/2, v = u+1, then u^2(mod p) = v^2(mod p) if and only if 'p' is a...

Jan1613 02:49 AM
dodo

1 
955 
hey guys
given Ax=B where A is a square matrix and x and B are vectors, can anyone tell me why a singular matrix...

Jan1613 08:38 PM
joshmccraney

3 
1,065 
Following is a list of 39 Mersenne numbers. Some are prime and some are not. These are generated with x =(...

Jan1713 08:06 AM
arydberg

6 
1,352 
Prove the Generalized Associative Law for Groups (i.e. a finite sum of elements can be bracketed in any way).
The...

Jan2013 12:55 PM
Fredrik

6 
1,581 
Hi all,
I searched all other threads but was unable to find something useful. Here is my question: I am looking...

Jan2013 03:06 PM
Wrukproek

0 
670 