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visits member for 2 years, 7 months
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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.


6h
comment Complex numbers in polar form
@Gummybears - Yes! You can use the notation of the exponent as others have if you wish - then you use the rules you already know (such as how to multiply them)
7h
comment Complex numbers in polar form
@MJD - Thanks for the edit. I don't have the \cis command in Lyx but its on Math.SE (apparently)
1d
comment Find the supremum of $\frac{t^{8/3}}{10 t^{8/3} + 1}$
@Mathmo123 - even better than what I did :)
1d
comment Find the supremum of $\frac{t^{8/3}}{10 t^{8/3} + 1}$
@Mathmo123 - I suggested this hint to help show it is monotonically increasing, it is easier to see it when we look at the function with $x$, IMHO
1d
comment Number of complex numbers such that $z^{80} = 1$ and other properties
Note that when we have real roots than we may have an odd number of roots - such as in the case of $z^3=1$
1d
comment Why in open balls is radius $r>0$?
@mle if $r=0$ then only $c$ is in the ball
Jun
26
comment Commutative permutations
@user159519 - I am working with $G=S_n$
Jun
26
comment Commutative permutations
@user159519 - Please try a little bit more and write down what you tried so I can better direct you. I think it will help more then writing down the answer..
Jun
21
comment $A$ matrix, $+i, -i$ are eigenvalues.
@user3628041 note that the determinant is zero iff one of the eigenvalues is zero and use Surb answer to complete the argument that indeed the implication I made holds
Jun
21
comment How on earth will anyone prove $n^3-3n^2+n-1=Θ(n^3)$
Yes you can, it follows from the definition
Jun
14
comment $T: M_{2\times 2}(R) \rightarrow M_{2 \times 2}(R)$ linear map
@IlanAizelmanWS use the standard basis (all entries are 0 except for one entry which is 1). Work with 4 dimensional coordinate vectors to represent an element of V
Jun
14
comment Matrix $A$ with characteristic polynomial
@IlanAizelmanWS - What book are you using ?
Jun
14
comment Matrix $A$ with characteristic polynomial
@IlanAizelmanWS - oh yes, your'e right
Jun
14
comment Matrix $A$ with characteristic polynomial
@IlanAizelmanWS - Good luck! Its a great course in my opinion
Jun
14
comment Matrix $A$ with characteristic polynomial
@IlanAizelmanWS - No, I deduced that because the dimension of the matrix is the same of the degree of the characteristic polynomial
Jun
14
comment Matrix $A$ with characteristic polynomial
@IlanAizelmanWS - By the way, do you study for the "Algebra aleph" exam ?
Jun
14
comment Matrix $A$ with characteristic polynomial
@IlanAizelmanWS - Yes. This would imply that the geometric multiplexing is $\leq 1$. But you also know that it is at least $1$ since it is an eigenvalue and so the geometric multiplexing is $1$
Jun
14
comment How to check whether this matrix is diagonalizable or not.
@David - I have shown a matrix $A$ with $A^3=-1$ but not the eigenvalues are not distinct. This is a counterexample for statement $1$
Jun
14
comment How to check whether this matrix is diagonalizable or not.
@Surb - a scalar $c$ means, in abuse of notation, $cI$
May
19
comment b such that Ax = b has no solution having found column space
@HenningMakholm thanks for the correction , you're right! I'll edit my answer