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I have a B.Sc in computer science and a B.Sc in mathematics from the Technion.

I am interested mainly in abstract algebra and I hope to start graduate school soon to continue study some advanced topics in this area.

Currently I am going over Abstract Algebra by Dummit and Foote to recall old topics and fill some gaps I have, while working full time as a programmer.


Oct
14
comment Eigenvectors of $\left( \begin{array}{ccc} a & 0 \\ 0 & -b \end{array} \right)$
Yes. that is $v=(1,0)^T$ imply $0v=0$ - not the other way around as you wrote it
Oct
14
comment Eigenvectors of $\left( \begin{array}{ccc} a & 0 \\ 0 & -b \end{array} \right)$
No - it is indeed a solution, but $0v=0$ does not imply $v=(1,0)^T$ , it doesn't say anything about $v$
Oct
14
comment Eigenvectors of $\left( \begin{array}{ccc} a & 0 \\ 0 & -b \end{array} \right)$
Oh sorry, but then I would argue that if $a=-b$ the implication is not correct
Oct
14
comment Eigenvectors of $\left( \begin{array}{ccc} a & 0 \\ 0 & -b \end{array} \right)$
If $a=b$ we get the zero matrix so the implication that $v=(1,0)^T$ in the first line is not correct
Oct
14
comment Eigenvectors of $\left( \begin{array}{ccc} a & 0 \\ 0 & -b \end{array} \right)$
assuming $a\neq b$ otherwise there are two independent solutions
Oct
14
revised Statistics book recommendation
edited tags
Oct
14
revised Group isomorphisms and a possible trivial statement?
deleted 2 characters in body
Oct
14
answered Group isomorphisms and a possible trivial statement?
Oct
14
revised Prove sequence $S_n$ converges
edited title
Oct
14
comment Prove sequence $S_n$ converges
possible duplicate of $\sqrt{c+\sqrt{c+\sqrt{c+\cdots}}}$, or the limit of the sequence $x_{n+1} = \sqrt{c+x_n}$
Oct
14
comment A real matrix whose eigenvalues have all negative real parts
I don't know about the ODE part but as a linear algebra claim it is false - actually your method shows any non invariable matrix with eigenvalues with negative real parts can be an example
Oct
13
comment How to find $(Ker(A^{*}))^{\perp}$
@ECE - the basis for the perpendicular space is not 'everything else' - it is a set with only two vectors (it is rather a basis for 'everything else')
Oct
13
answered What is a “formal definition” of a set?
Oct
13
comment What is a “formal definition” of a set?
I removed the Formal Languages tag. Tag wiki is - Formal languages are studied in computer science and linguistics. They are usually defined using various types of grammars (e.g. regular, context-free) and automata (e.g. deterministic and pushdown automata, Turing machines). There is a hierarchy of formal languages, which is based on the type of grammars and automata which can be used to generated them.
Oct
13
revised What is a “formal definition” of a set?
edited tags
Oct
13
answered How to find $(Ker(A^{*}))^{\perp}$
Oct
13
comment Fractional parts in base number systems other than base-10?
@Eliot - See my comment
Oct
13
comment Fractional parts in base number systems other than base-10?
This answer is not correct, $1.11 = 1*2^0 + 1*2^{-1}+1*2^{-2}$ this is analog to the decimal system where for example $1.57=1*10^0+5*10^{-1}+7*10^{-2}$
Oct
13
reviewed Approve suggested edit on Are the expression $E_1$ and $E_2$ both indivisible by all primes till $p$ if $\cdots E_1=$ and $E_2=$
Oct
13
comment How can we find an element of largest order in $S_n$ in general?
@following rogerl link - oeis.org/A000793