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

Feb2313 09:24 AM
micromass

1 
35,917 
If A\in\mathbb{C}^{N\times N} is some complex matrix, is there anything we could say about the determinant of the...

Dec2212 08:15 AM
sfn17

2 
5,320 
Hi, I was playing with Riemann zeta function on mathematica. I encountered with a quite interesting result. I iterated...

Dec2212 09:48 PM
Jeff Cook

10 
2,082 
Let B={b1,b2} and C={c1,c2} be basis. Then the change of coordinate matrix P(C to B) involves the Ccoordinate vectors...

Dec1912 10:20 PM
bonfire09

2 
1,029 
Apart from simplifying matrix powers, why do we want to diagonalize a matrix? Do they have any appealing application...

Dec2212 06:03 PM
marxLynx

4 
1,278 
I know that we say two representations R and R' of a group G is equivalent if there exists a unitary matrix U such...

Dec2112 07:51 PM
micromass

2 
816 
Hello everyone, first time poster, long time reader here!
I'm an exmath major and while I'm no longer pursuing a...

Dec2112 04:15 PM
johnqwertyful

5 
1,082 
Hey all, I have been playing around with a special type of matrix and am wondering if anyone knows of some literature...

Dec3012 11:21 PM
orthogonal

4 
1,474 
I am reading linear algebra by Georgi Shilov. It is my first encounter with linear algebra. After defining what a...

Dec2112 06:23 PM
Fredrik

5 
1,220 
Getting ready for linear algebra exam. One question that I got right but not exactly sure why is this:
...

Dec2112 03:38 PM
Frogeyedpeas

4 
1,092 
I have been trying to prove the following result:
If A is real symmetric matrix with an eigenvalue lambda of...

Dec2212 04:54 AM
matqkks

2 
1,047 
What is the best way of introducing singular value decomposition (SVD) on a linear algebra course? Why is it so...

Dec2212 03:19 PM
Stephen Tashi

2 
762 
Imagine we have two operators A and B on a complex hilbert space H such that:
\psi = (ABBA) \psi=c \psi \ \ \ \...

Dec2212 10:42 PM
micromass

6 
1,113 
Prof. Hugh Montgomery has been quoted as saying that it appeared that, if the Riemann hypothesis is true, the...

Dec2312 10:37 AM
nomadreid

0 
870 
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 
1,390 
Hello,
I was wondering, why is the vector projection useful in the way that it is presented? Why isnt just the...

Dec2712 03:30 AM
Stephen Tashi

12 
2,226 
Question is :
If m,k,n are natural numbers and n>1, prove that we cannot have m(m+1)=kn.
My attempt :
Using...

Dec2712 12:16 PM
mathwonk

16 
2,998 
I have an equation (constraint) which I wish to solve explicitly in terms of gd (or more precisely a scaling factor of...

Dec2512 02:42 AM
james1234

1 
862 
Video illustration
Hello,
Me and a friend, David Barrack, are nonmathematicians but we've been having fun...

Dec2512 11:34 AM
micromass

2 
2,050 
I was looking for a hint on a problem in my professor's notes (class is over and I was just auditing).
I want to...

Dec2812 06:42 AM
sammycaps

12 
1,306 
The logic that odd composite with least difference will be factored easily and large difference would factored hardly...

Jan113 09:30 AM
mfb

4 
1,647 
I've got a general question about Lie algebras, which is basically this:
Q: What is there to be said about the Lie...

Dec2712 01:10 AM
Couchyam

0 
761 
This may be a very silly question, but still apologies, I read in Sheldon Axler, that the inner product of two...

Dec2712 07:31 AM
vish_maths

3 
858 
The book I am going through says this :
The below proposition is false for real inner product spaces. As an...

Dec2812 06:46 PM
chiro

3 
999 
Is there any algorithm to form a magic square of any size with a desired magic sum ?
Also can we make a magic square...

Dec3012 08:09 AM
RamaWolf

6 
2,128 
Hi All,
I have a hard time answering the following. I need some help.
Let Z={a,b,c,d,e,f} and let X denote the...

Dec3012 01:31 PM
laptopmarch

1 
752 
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 
1,562 
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 
807 
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 
2,253 
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 
1,017 
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 
2,352 
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 
924 
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 
767 
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 
1,634 
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 
1,000 
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 
923 
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 
837 
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 
1,146 
I have no idea what this is! Please can someone explain comparing to a 3x3 matrix?

Jan613 05:19 PM
mfb

3 
1,106 
No not the trival solution but generally GCD(x,y) = 1 when GCD(A,B)=1
x =...

Jan713 12:40 AM
ramsey2879

0 
1,010 
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 
571 