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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.


Dec
12
comment If $\int_A f=0$ for every measurable subset $A$ of $E$, then $f(x)=0$ a.e. on $E$
Although I agree the conclusion follows from whats written, I think that it doesn't follow from the last line about $mesE$ in the case that $E$ is of infinite measure, instead I think it would be better to write that the set of points in $E$ s.t $f$ is non-zero in are the union of $A_n,B_n$ and so by sigma additivity it have measure 0
Dec
12
comment If $\int_A f=0$ for every measurable subset $A$ of $E$, then $f(x)=0$ a.e. on $E$
@DavidMitra - but it was not mentioned that $f>0$
Dec
7
comment Can the equation $\mathbf{Av}=\mathbf{b}$ be solved as $\mathbf{v}=\mathbf{A}^{-1}\mathbf{b}$?
It's worth mentioning that there may be a solution even if A is not invertiable, the Matlab code example try to find such a solution
Dec
6
comment Do I need to evaluate exact value of $A^9$ to find $Det.(2A^9B^{-1})$?
Check the question: B is not invertiable and A can not be squared
Dec
4
comment How to obtain and graph a function that first grows exponentially and then decays exponentially?
wolframalpha.com/input/?i=x%5E2
Nov
28
comment Topic for a lecture intended for High School students
How about basic graph theory? Definitions and proofs can be made graphic and can be more easily thought
Nov
17
comment Eigenvalues of this 3x3 matrix
It would help if you write what you did so we can help find the error and lead you in the right direction
Nov
17
comment Show that there exists a polynomial such that..
In all uses, zero should be a, right?
Nov
16
comment Proving that $x^3 +1=15x$ has at most three solutions. in the interval [-4,4].
@YellowSkies - This is a very important theorem, you should at least learn its statement
Nov
1
comment 1. Given a group homomorphism $\psi: A_{8}\rightarrow S_{9}$ for which exists $\sigma\in A_{8}$ with $\psi(\sigma)=(12)$
an isomorphism to its image, not all of $G_2$ (this is practically the first isomorphism theorem applied to this case)
Nov
1
comment Distance of a point from a line
I don't understand, from "the dot product of two unitary vectors" I get that $A-M$ is a unit vector, why is that ? secondly, I don't understand why the said projection equals to the distance of $M$ from the line (did you mean $A$ ?, I would still not understand why, but $A$ makes more sense to me)
Oct
31
comment Checking irreducibility of $3x+6$ in $\mathbb Q[x]$ and $\mathbb Z[x]$
@patang - Herbert Quain answers add to mine. He gave you a factoring over $\mathbb{Z}$ and claimed it does not exist over $\mathbb{Q}$.
Oct
25
comment Let $p,q$ are distinct primes and $G$ be a group of order $pq$ then which of the following is true?
How does this help?
Oct
25
comment Equal integrals, circles, opposite directions
@Hagrid - This is part of the question that asks you to understand that going over this circle the other way around (i.e clockwise and not anti-clockwise) means that the integral value would be minus the value were we to go over the path the regular way
Oct
25
comment Equal integrals, circles, opposite directions
@Hagrid - Yes, you got it right!
Oct
25
comment Finding $\sum \frac{1}{n^2+7n+9}$
@Pkwssis - Using a partition of $[0,1]$ to $n$ parts with equal length
Oct
25
comment Extension field, degree of $[\mathbb Q(i,\sqrt{-3}):\mathbb Q]$
@idm - Because both $i,\sqrt{-3}\in\mathbb{Q}(i,\sqrt{-3})$ and it it closed under addition (since it is defined to be a field)
Oct
24
comment $27 | (2x+1)^2 \implies 2x$ is a multiple of 9?
@MJD - Why not post this as an answer ?
Oct
24
comment Why is any subspace affine?
This looks like the definition of convexity not of affinity..
Oct
23
comment For all $X \subseteq \mathbb{N}$ there exist $n \in \mathbb{N}$ with $|X| < n$.
Yes. And for your choice there are infinite number of subsets, given any k there is the subset of all element smaller than k. So there is at least one subset per Natural number and thus infinite number of subsets