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

Feb2313 09:24 AM
micromass

1 
30,432 
Hello, everyone.
I have a n*n Toeplitz block matrix of basic dimension m*m. If it is not a block matrix, I can use...

Jun1009 12:14 AM
BiBByLin

0 
1,065 
I really don't know which section this should be posted in.
I spent some time yesterday dividing by zero in an...

Jun809 06:49 PM
Phrak

6 
1,580 
Hi! I wonder if you guys help me prove this:
span(S1 ∩ S2) ⊆ span(S1) ∩ span(S2)
I have seen span(S1 U S2) =...

Jun809 03:55 AM
MathematicalPhysicist

1 
2,008 
I have a block Toeplitz matrix with complex parameter
as shown in attachment file.
How can I solve such problem, I...

Jun709 10:53 PM
BiBByLin

0 
784 
I am studying invariance, and I came across this dilemma.
Suppose we have a subspace with the basis <v1, v2> of the...

Jun609 06:46 PM
evilpostingmong

2 
794 
First Question:
Let Nn be the integer whose decimal expansion consists of n consecutive ones. For example, N2=11 and...

Jun609 03:45 PM
ramsey2879

7 
1,734 
Hi.
Need help with following problem:
Let R=(V,E) a regular graph with degree at least 1 and odd number of...

Jun609 12:00 PM
Geomancer

1 
953 
Prove whethere is linearly independent or not the following:
{e^x,e^{2x}}

Jun509 09:15 PM
evagelos

29 
2,498 
Hello,
Can someone help me understand why the Inner Product of a Null vector with itself can be non zero if complex...

Jun509 12:22 PM
DeepSeeded

3 
2,802 
So I've been working through some algebraic number theory and there is a problem asking me to describe the ideals in...

Jun509 10:08 AM
sidm

0 
1,534 
Can it be proven that the number of prime pairs with a difference of two (that is, primes separated by only one even...

Jun409 04:53 PM
HallsofIvy

6 
1,755 
Theorem 5.3: Let A be in M_n_x_n(F).
(a) The characteristic polynomial of A is a polynomial of degree n with leading...

Jun109 08:39 PM
jeff1evesque

6 
2,962 
Hey
Does anyone know where I can find the generators of the group of rotations in four dimensions?
thanks!

Jun109 11:37 AM
George Jones

3 
1,292 
in a seminar at my univesity we had a brief introduction to prime number theorem , in the blackboard the professor...

Jun109 04:53 AM
zetafunction

0 
1,262 
without using a counter example, show a proof that Euler's polynomial equation P(n)=n^2+n+41 can not be used to...

May3109 06:34 PM
CRGreathouse

14 
2,901 
my question is, let us suppose we can find an expansion for the prime number (either exact or approximate)
\pi...

May3009 12:24 AM
CRGreathouse

5 
2,073 
Hi all, I had a problem, pls help me.
Let b_1 < b_2 < \cdots < b_{\varphi(m)} be the integers between 1 and m that...

May2909 10:52 AM
whodsow

3 
6,233 
The HelmannFeynman theorem states that :
derivative of eigenvalue with respect to a parameter = eigenfunction dagger...

May2909 10:48 AM
juliette sekx

5 
2,164 
I am just curious. If I have a random number generator, eventually, if I wait long enough all possible numbers should...

May2809 09:01 AM
CRGreathouse

126 
26,122 
Is it true that if \sigma \in S_n is a cycle of length k \leq n, then \sigma^k = \varepsilon, where \varepsilon is the...

May2809 01:04 AM
matt grime

5 
1,310 
"Of the numbers N>1, only 4 and 6 cannot be expressed as a sum of prime numbers with unique values."

May2709 11:26 AM
Loren Booda

2 
1,309 
hi,
what is wrong about this proof?
If x^TAx=0 then A is antisymetric matrix. True? false?
P: False
A=A^T...

May2709 10:36 AM
jbunniii

3 
1,247 
Question:
Can someone explain the following to me: "... the entries of the matrix A  tI_n are not scalars in the...

May2709 10:25 AM
HallsofIvy

5 
1,546 
Does either
\frac{\prod_{2N=n}^\infty{p_n}}{\prod_{2N1=n}^\infty{p_n}}
or
...

May2709 10:08 AM
John37

8 
2,535 
On average, at least how many factors must one try dividing a number N by to decompose it into primes?

May2609 11:07 PM
CRGreathouse

6 
1,723 
Is there a function f(x) that will give the average number of prime factors for x_1 0<x_1<x, in a way similar to the...

May2609 06:03 PM
CRGreathouse

7 
4,583 
Hello,
I don't want how to prove: Matrix A is nilpotent, so A^k=0. Prove that det(A+I)=0.
Thank you so much :)

May2609 01:34 PM
lukaszh

7 
1,311 
Hi,
Is there any solution for the following problem:
Ax = \lambda x + b
Here x seems to be an eigenvector of...

May2609 03:41 AM
ahmethungari

2 
903 
Why are they called "axioms"? Shouldn't they be called "definitions"?

May2609 12:20 AM
Dragonfall

16 
2,792 
Hi:
was wondering if somebody can help me with this I came across in a paper.
$e_k$ is a vector of $k$ $1's. M...

May2509 10:01 AM
alice20006

5 
2,984 
This seems a simple question but I am unsure as to why I cannot find a number n where
2^n mod 3 = 0
I am trying...

May2409 11:29 PM
xnull

13 
6,044 
the question is, i wish to calculate the sum
\sum_{ n=1}^{N}a(n) for big N
then you can introduce a so called...

May2409 03:49 PM
zetafunction

0 
1,147 
if x is an integer,
x1=6x2+8x+2
x2=6x21+8x1+2
x3=6x22+8x2+2
x4=6x23+8x3+2
x5=6x24+8x4+2
if i want to see x5 in...

May2409 11:15 AM
chhitiz

6 
1,508 
I have a problem.
Calculate Dim(Ran(T)) if T is 1to1. Also calculate Dim(Ker(T)) if T is onto.
How do you think I...

May2409 07:43 AM
HallsofIvy

2 
4,747 
Hello,
I was reading something in my text/wikipedia, and they both said that "...the eigenvalues of a matrix are...

May2309 06:40 AM
HallsofIvy

2 
1,135 
grad(A*B)=(A*grad)B + (B*grad)A + A curl B + B curl A
i'm not sure how to read the RHS to begin to work out the...

May2309 03:11 AM
dx

1 
1,167 
Does anyone know of a source with a list of unsolved problems in those fields? Not "wellknown" problems like the...

May2209 10:22 PM
Dragonfall

0 
2,452 
I was just wondering how you know if linear transformations injective?

May2209 09:02 AM
HallsofIvy

3 
2,621 
Suppose you had the following:
(A,*) and (B,\nabla)
So to prove associativity, since I know that both A and B...

May2109 04:33 AM
tinytim

6 
2,279 
Notations:
σ denotes an Rmap
M denotes an abelian group under addtion
R denotes a commutative ring with identity...

May2009 09:02 PM
sanctifier

2 
1,546 