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

Feb2313 09:24 AM
micromass

1 
35,198 
I'll start off with my question:
Why do we use Gaussian Elimination when inverting a matrix? (this is only one of...

Oct110 08:50 AM
HallsofIvy

2 
1,188 
I have a question regarding the GramSchmidt process. When solving for the new subspace, is it okay to make a newly...

Oct110 12:45 PM
gbartel

2 
935 
We have W = 1,v2,v3,v4]
v1=ik
v2=i+j+k
v3=j+2k
v4=2i+j
Show that W is a subspace of V3.
first, vector 0 is...

Oct210 08:37 AM
arkajad

4 
956 
I would like to show that (cxb).a = (axc).b in Rn where x denotes the cross product and . denotes the dot product.
...

Oct210 08:56 AM
BruceG

2 
999 
Hello,
I read somewhere that the set of unit quaternions identifies the \mathcal{S}^3 sphere.
This makes sense;...

Oct210 03:17 PM
mnb96

12 
1,917 
what is the maximum number of terms can a arithmetic progression of only prime numbers have?

Oct210 09:20 PM
sachinism

2 
2,251 
Huzzah.

Oct310 05:26 AM
Simon_Tyler

1 
912 
Gracias

Oct310 11:13 AM
HallsofIvy

1 
1,044 
Hi all,
I've been reading up on ways of factorising numbers through the congruence of squares method...

Oct310 12:15 PM
Mathmos6

1 
1,920 
Hai friends
I am aravind,doing post graduate in computer science .In this thread I explain about the...

Oct310 03:39 PM
Devhans

11 
4,449 
Sounds great thank you

Oct310 04:28 PM
Simon_Tyler

3 
1,141 
How do we know that the cartesian product of any two groups is also a group using the axioms of group theory?

Oct310 05:58 PM
Landau

6 
2,344 
I read the following on the wikipedia page about simple rings (http://en.wikipedia.org/wiki/Simple_ring):
I do...

Oct310 10:32 PM
gerben

3 
1,103 
Lets say I have a 3x3 matrix 'A' and one known eigenvalue 'z' and one known eigenvector 'x', but they don't "belong"...

Oct410 12:35 AM
Simon_Tyler

7 
1,749 
Hello everyone, I need some help with finding norms of the field extension.
I feel pretty comfortable when...

Oct410 11:08 PM
adriank

1 
838 
Hello everyone. I was going through my Linear Algebra Done Right textbook that threw me off. I hope this forum is...

Oct410 11:17 PM
adriank

3 
5,069 
dimension of sl(2,R) = 1*(2*21) = 3, is isomorphic to so(2,1) : 2+1 = 3
dimension of sl(2,C) = 2*(2*21) = 6, is...

Oct410 11:18 PM
BruceG

2 
1,505 
What could we say if a matrix is invertible? Could we say that it can span and is linearly independent?

Oct510 08:44 AM
HallsofIvy

1 
2,959 
Recently when I talked to a professor specialized in number theory, I learned about normal numbers.
So the other...

Oct510 05:34 PM
hamster143

8 
1,540 
Hi,
I need to do Interpolation of complex numbers let say
z1=x1+i*y1
and
z2=x2+i*y2
now I have two approaches:...

Oct510 05:42 PM
hamster143

2 
2,902 
This should be a simple question for anyone familiar with basic algebraic geometry, but the concept is getting the...

Oct510 08:02 PM
Newtime

5 
1,629 
consider a vector A
A = A(A dir)
here A dir is A with hat on...

Oct510 11:04 PM
Fredrik

5 
991 
I notice that the trick to define Dirichlet Eta Function can be repeated for each prime number, let p a prime, and...

Oct610 04:07 AM
arivero

0 
969 
Preface: I am an electrical engineer studying for the PE exam. I am reviewing power system analysis and have come...

Oct610 02:58 PM
MitYeltu

2 
1,197 
like N=5053=163*31 and N=169*37=6253 if we do not know the factors and if we do not want to factor them. They both...

Oct610 09:48 PM
epsi00

6 
1,226 
I am reading a paper where the author uses colons in the description of groups. Example (not verbatim): "This subgroup...

Oct710 10:23 AM
AgentBased

2 
1,967 
The formula used for linearization is y=(m)(Square root of x) + b correct?
How do I find the square root of x if...

Oct710 10:36 AM
HallsofIvy

1 
3,244 
Hello,
it is known that purequaternions (scalar part equal to zero) identify the \mathcal{S}^2 sphere. Similarly...

Oct810 01:21 AM
mnb96

10 
1,899 
Is it true that if a finite group G contains a subgroup of index 2, then there is an element of G with order 2?

Oct810 10:08 AM
ForMyThunder

3 
816 
Is it possible to write the 2010 numbers from 1 a 2010 in some order so that the
6933 digit number you get is prime?

Oct810 07:25 PM
Wizlem

11 
1,653 
Hello,
let's consider, for example, the Clifford algebra CL(2,0) and the following mapping f for an arbitrary...

Oct910 03:59 AM
mnb96

4 
1,539 
I know about using projector decomposition in diagonalization, but
I heard from a friend about finding a 2x2...

Oct1010 02:21 AM
while.awesome

0 
700 
I am interested in twin primes and have not been able to find a simple "sieve" type function to calculate them.
I...

Oct1010 09:27 AM
toddkuen

2 
2,505 
Let G be the group of 2x2 invertible upper triangular matrices and H be the group of 2x2 invertible lower triangular...

Oct1010 06:26 PM
symbol0

4 
1,686 
I saw the following problem on my abstract algebra book (dummit && foote) , I tried to solve it but I couldn't :
Let...

Oct1110 04:03 AM
hermanni

3 
1,729 
Is there a tool that spits out a general polynomial formula for an input consisting of a finite sequence, e.g.:
you...

Oct1110 09:38 AM
epsi00

6 
3,571 
Hi out there peps, very nice forum! (my first topic)
Atm Im dealing with complex numbers, and Ive got kinda problem...

Oct1110 10:03 AM
palaszz

2 
1,231 
so i've been reading jim hefferon's linear algebra book
i dont know if anyone on the forum has seen it, but im only...

Oct1110 11:24 AM
miglo

4 
916 
First it must has char.poly x^2*(xc), then c must be zero because char. poly and min. poly have the same roots.
...

Oct1110 03:13 PM
ivyhawk

0 
1,533 
Hello PhysicsForums.com!
I've got several sets of data that are all intended to represent the same ideal data set....

Oct1110 03:21 PM
phrozenfearz

2 
726 