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

Feb2313 09:24 AM
micromass

1 
34,334 
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 
4,790 
fin all natural numbers n that n\sigma (n) \equiv 2(mod\varphi(n))

Nov2109 05:51 PM
hamster143

5 
1,466 
There is something I don't understand about the recent concept of a "number derivative". It seems to me that the (very...

Nov2109 06:01 AM
dodo

0 
1,401 
If C = A +B where A,B are both p.d, than C is p.d and its eigenvalues are positive.
Waht can you say about the...

Nov2009 02:16 PM
trambolin

2 
3,539 
what is it?

Nov2009 12:46 PM
ramsey2879

2 
1,663 
Hey guys i am stuck with the gaus jordan method of the following matrix.
A = 1 2 3
4 5 6
3 1 2
For the co...

Nov2009 05:56 AM
HallsofIvy

1 
1,886 
Here is an interesting problem I came up with during my research. I first present a slightly simplified version. Let...

Nov2009 03:53 AM
topcomer

1 
1,632 
Hi all,
I've been staring at this question on and off for about a month:
Suppose that p is an odd prime, and g...

Nov1909 07:34 PM
ramsey2879

4 
2,940 
For those of you with "A First Course in Abstract Algebra 7th ed.," I'm on chapter 15 and in particular, the first 12...

Nov1909 06:01 PM
Newtime

3 
1,885 
Construct a sequence that visits the numbers 0,1,5 infinitely often.?
A sequence Sn visits a number A when for...

Nov1909 12:46 PM
ramsey2879

9 
1,501 
Hello,
I am quite new to Geometric Algebra, this is the reason for the silly question.
In Geometric Algebra, the...

Nov1909 04:24 AM
mnb96

1 
909 
Hi All,
Is there a module such that the torsion elements do not form a submodule? Do they always form a submodule?...

Nov1809 06:08 PM
esisk

0 
827 
Assuming A is a 2x2 matrix how many different matricies exist such that A^2=I ?
I am 99% sure the answer is 4 but...

Nov1809 04:16 PM
D H

4 
1,156 
my idea is, if we consider the geometry of primes could we conclude they form a fractal ? , for example if we...

Nov1809 09:21 AM
Rogerdoger

4 
5,104 
Proposition. A polynomial of degree 2 or 3 over a field F is reducible iff it has a root in F.
Tell me if I'm on...

Nov1809 05:51 AM
HallsofIvy

1 
743 
Hi!
I am working on the following problem:
If a matrix is antisymmetric (thus A^T = A), show that
P = {A...

Nov1709 04:08 PM
chefobg57

6 
1,253 
think i have discovered an integral equation for the Xifunction
\Xi (z)= A\int_{\infty}^{\infty} \phi...

Nov1709 09:19 AM
zetafunction

1 
1,715 
Hay all, I am stuck on a problem, and its driving me crazy. I have a problem, xN = a mod b. Where I have to solve for...

Nov1709 07:48 AM
CRGreathouse

5 
1,877 
So I just bought his ook called "Matrices and Linear Algebra" by Hans Schneider and G.P. Barker in an attempt to teach...

Nov1709 06:35 AM
Ruslan_Sharipov

14 
3,444 
Hi, I'm a grad student in pure math and I'm trying to relearn my linear algebra from scratch because I never learned...

Nov1709 06:25 AM
Ruslan_Sharipov

7 
10,061 
Let me start off by saying I have not yet had a formal course in Number Thoery and have only read briefly on the...

Nov1609 07:33 PM
gcsetma

3 
2,189 
If I have n runners on a circular tracks at different speeds s_i, will they always meet up arbitrarily close together...

Nov1609 11:34 AM
Gerenuk

9 
1,708 
hey,
how can ı show the reflections over the line do not have group structure?
reflection of the real plane...

Nov1609 10:54 AM
tinytim

1 
884 
how to find number (3i)^{12} ?
i know theorem for powers of complex numbers, but i have to know argument of...

Nov1609 08:34 AM
g_edgar

1 
1,327 
Let V be a finite dimensional complex inner product space with inner product < , >. Let U be unitary with respect to...

Nov1609 07:40 AM
e(ho0n3

4 
1,796 
Hi everyone,
I saw that for the linear diophantine equation d=ax+by, where d=(a,b), that x and y must be coprime.
...

Nov1409 08:10 PM
thomas430

2 
2,104 
We have three orthonormal vectors \vec i_1 , \vec i_2, \vec i_3 , and we know wich are the components of an...

Nov1409 03:18 PM
jonjacson

3 
1,472 
(1+2+....n)^{2} = 1^{3}+2^{3}+...n^{3}
\frac{n^{2}(n+1)}{4}^{2} = 1^{3}+2^{3}+...n^{3}
how do you simplify the...

Nov1409 02:42 PM
D H

7 
5,328 
Is the derivative operator d/dx bounded with respect to the norm <f,g> defined by
integral from 0 to 1 of f g*...

Nov1409 01:01 PM
esisk

2 
1,287 
hi can someone tell me...how to correctly use the 10 axioms..
for example: does the set of all 3x3 symmetric matrices...

Nov1409 04:11 AM
HallsofIvy

3 
2,568 
I'm going to be doing research next semester on a topic of almost entirely my choice. I'd like to research anything...

Nov1309 03:07 PM
Newtime

3 
1,644 
First, sorry for my poor English and any impolite behavior might happen.
Here's two wave function(pic1) and problem...

Nov1309 07:56 AM
boladore

0 
2,849 
I'm trying to show that a set W of polynomials in P2 such that p(1)=0 is a subspace of P2. Then find a basis for W...

Nov1309 06:00 AM
HallsofIvy

11 
4,626 
The question posed is "Classify up to similarity all 3 x 3 complex matrices A s.t. A^{3} = I. I think the biggest...

Nov1109 09:17 AM
g_edgar

4 
2,492 
Hi,
I've been trying to show that the set of matrices that preserve L1 norm (sum of absolute values of each...

Nov1109 09:11 AM
g_edgar

5 
3,249 
I'm looking at the exercises of Hungerfod's Algebra. Some looks easy but it seems the proofs are not so obvious....

Nov1109 12:27 AM
Spartan Math

4 
7,201 
i)]+1=0 :I had a friend with a Tshirt displaying this deceptively simple equation. I know it to be true, but I have...

Nov1009 06:23 AM
widewombat

51 
23,259 
can explain to me what is mean of span?
from book, it say "every vector in the space can be expressed as linear...

Nov1009 01:02 AM
Dafe

6 
1,587 
If I have a matrix A, and I use n different row operations of this form: a_kR_i + R_j \rightarrow R_i to construct a...

Nov909 08:01 PM
slider142

5 
998 
The positive powers of 2 mod 5^m cycle with period 4*5^(m1), which you can prove by showing that 2 is a primitive...

Nov909 10:59 AM
DoctorBinary

8 
5,119 