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

Feb2313 09:24 AM
micromass

1 
35,963 
Hi this is my first post on this site and glad to be here!
Ive only really started looking into maths and physics...

Sep2112 10:05 PM
bahamagreen

5 
2,090 
Hello
I'm reading my old notes of QM, I found the definition of Pauli vector, as follow
\vec{\sigma}=\sigma_1...

Sep1812 10:42 AM
dextercioby

4 
2,107 
Hey all,
I am trying to get a head start on Linear Algebra before i start taking classes in a couple weeks. I am...

Sep1612 09:51 PM
homeomorphic

10 
5,477 
Hello Forum,
a system of linear equations can be determined (if there are as many unknowns as equations),...

Sep1712 10:56 AM
fisico30

15 
2,648 
Consider the separation of the Riemann Zeta function in two terms
\begin{flalign*}
\zeta(s) &= 1^{s} + 2^{s} +...

Sep1912 04:01 PM
arivero

3 
2,175 
I know that one of Goldbach's conjectures is that every even number is the sum of 2 primes.
So, I was wondering if...

Sep2212 01:48 PM
Norwegian

6 
4,245 
Hi all. I'm studying from Leon's Linear Algebra with Applications. I'm wondering if one of his examples has an error....

Sep1812 11:37 PM
chiro

4 
1,392 
I can easily visualize the 3 dimensional way to do so, and already have.
I'd like to rotate from the...

Sep1912 12:24 AM
chiro

2 
1,029 
Hi, I have a problem from a textbook on control systems along with the solution, but I'm not certain how the answer...

Sep2412 10:52 AM
The Electrician

7 
1,404 
I am trying to prove that 11 is a prime in \mathbb{Z}.
I noticed that \mathbb{Z} is not a UFD so I cannot show that...

Sep1712 11:42 AM
mathwonk

2 
1,100 
I have a matrix A with real values that I wish to decompose into a proper orthogonal matrix R and a symmetric matrix...

Sep1712 01:15 AM
Bavid

0 
863 
I'm trying to find if a number is odd or not, basically if X % 2 = 1.
Can this be expressed through some function?...

Sep2512 08:48 AM
Eval

13 
2,167 
Hi. I'm wondering if anyone can point me to any information on techniques to decompose a matrix (actually a 3D...

Sep1712 03:04 PM
Stephen Tashi

6 
1,880 
Let
$${x_1,x_2,...x_n}$$ be positive numbers. Consider the matrix C whose (i,j)th entry is ...

Sep1712 10:21 AM
dsantanu

0 
802 
Why are QR factorization useful and important?

Sep1812 11:05 AM
hotvette

1 
719 
Hello,
Scilab help states that If a matrix is badly scaled or nearly singular, a warning message will be...

Sep2312 11:46 AM
sunny110

14 
4,739 
Say I have a mxn matrix A and a nxk matrix B. How do you prove that the matrix C = AB is fullrank, as well?

Sep2212 03:13 PM
AlephZero

6 
2,153 
In 'Linear Algebra Done Right' by Sheldon Axler, a direct sum is defined the following way,
We say that V is the...

Sep1912 02:02 PM
omoplata

2 
742 
Am I right in saying that Zp x Zp (the product of the integers mod p, a prime, with itself) has only 3 nontrivial...

Sep1912 09:41 PM
carrie.lugo

2 
1,238 
How can I prove that the set of all planar vector fields forms a vector space? Thanks for any input!

Sep2012 12:50 AM
mathwonk

2 
1,458 
I have array of natural numbers from 1 to n.
They are divided into m groups, where m*(m1)=n.
I need all m1...

Sep2112 05:10 PM
martika

2 
1,595 
I would like to find a 3D coordinate of a point (X) on a circle, knowing two points on the circle (P1,P2) which...

Sep2212 10:24 PM
alaam2005

6 
1,757 
Suppose there is a set of complex variables
\{x_i,\,i=1 \ldots M;\;\;y_k,\,k=1 \ldots N\}
and a polynomial...

Sep2412 04:08 AM
chiro

5 
1,082 
Does anyone know of a general approach towards the problem posted here:
http://proteneer.com/blog/?p=1557
It...

Sep2112 05:02 PM
exmachina

0 
623 
I'm reviewing Projective Geometry. This is an exercise in 2D homogeneous points and lines. It is not a homework...

Sep2212 05:40 PM
Muphrid

5 
1,219 
Hello forum,
why does a system of linear equations really have no solution or one unique solution, or infinite...

Sep2312 02:42 PM
Studiot

7 
1,145 
I have to prove "For every integer n, n^2 is congruent to exactly one 0,2,or 4mod 7? I don't even know where to start?...

Sep2612 05:17 PM
ramsey2879

17 
2,784 
Find two algebraic numbers (over Q) a and b each of degree 3 such that ab has degree 2.
I have attempted to...

Sep2412 10:04 AM
bessletama

0 
580 
Okay, so for the problem before this, I proved that L(S ∩ T ) ⊂ L(S ) ∩ L(T ).
For this problem, I have to give...

Sep2312 09:42 PM
TrapMuzik

1 
624 
Hi
Can someone please clarify if you are trying to diagonalize a matrix and you find that one of your eigenvalue is...

Sep2412 04:58 PM
HallsofIvy

4 
959 
Hi,
A quick question:
Does a set need to be a subset to be a subspace of some vector space?

Sep2412 09:22 AM
Max.Planck

3 
773 
Prove that the polynomial $$x^{20}2x^{13}+10x^{7}6x^{2}4x+100\in\mathbb{Z}$$ is irreducible or factors into...

Sep2412 09:57 AM
bessletama

0 
579 
Find the general solution to the following system of equations and indicate which variables are free and which are...

Sep2412 09:03 PM
Simon Bridge

1 
842 
u and v are contained in V
Lets say the scalar multiplication is defined as:
ex.
ku=k^2 u or ku =...

Sep2612 10:29 AM
Stephen Tashi

2 
1,153 
I'm required to diagonalize a 5x5 matrix by hand, using 'appropriate similarity transformations.' I'm not asking for...

Sep2612 05:02 PM
Robert1986

12 
1,917 
Hello,
I am reading a set of lecture notes on lattice QCD:...

Sep2612 09:58 AM
evilcman

0 
597 
I have had absolutely no sleep for a while, so my math brain has been failing me. Last night, I was working on a...

Sep2812 10:03 AM
ramsey2879

9 
2,370 
we know the equation above does not have integer solutions ( Fermat last theorem having been proven few years back )....

Sep2712 07:24 AM
epsi00

1 
1,465 
I am really confused about something. I know that if I have a vector space, then the dimension of that vector space...

Sep2712 10:09 PM
dumbQuestion

5 
883 
The assignment is making use of the property of triangular matrices to find the inverse of a matrix \displaystyle A. ...

Sep2812 07:07 AM
Ask4material

0 
719 