Reputation
1,372
Next privilege 2,000 Rep.
Edit questions and answers
Badges
7 12
Newest
 Nice Answer
Impact
~42k people reached

  • 0 posts edited
  • 0 helpful flags
  • 762 votes cast
Aug
27
accepted What is the injective envelope of a product of abelian groups?
Aug
27
comment What is the injective envelope of a product of abelian groups?
Never mind, I was being dense.
Aug
27
comment What is the injective envelope of a product of abelian groups?
This seems to work. One question, and I may just be being dense here: Why is the group $E$ divisible?
Aug
26
revised What is the injective envelope of a product of abelian groups?
Further clarification of question.
Aug
26
revised What is the injective envelope of a product of abelian groups?
clarifying the desired form of the answer
Aug
26
asked What is the injective envelope of a product of abelian groups?
Aug
4
comment Why is it that if one NP complete problem is solved, all NP problems are solved?
I believe the term NP complete was chosen because all NP problems can be realized as instances of the NP complete problem.
May
4
comment For a polynomial $f\in K[x]$, when is there a constant $c\in K$ such that $f+c$ is irreducible?
Suppose $K=\mathbb{C}$. What are the irreducibles in this case?
Apr
15
comment Subgroups of $ \mathbb{Z}_n$ (integers mod $n$)
Following up on what @quid said, $m$ and $n$ will generate the same subgroup of $\mathbb{Z}_{18}$ if and only if $\gcd(m,18)=\gcd(n,18)$, which you may verify by listing all the cyclic subgroups of $\mathbb{Z}_{18}$. You may restrict each of $m$, $n$ to be in $\mathbb{Z}_{18}$ of course.
Feb
9
comment Non abelian subgroup of a abelian group.
You can have abelian subgroups in a non-abelian group, but not non-abelian subgroups in an abelian group.
Jan
18
comment is complex number under absolute value a group?
Is the number 0 allowed? If so, what is its inverse?
Dec
29
comment Why rationalize the denominator?
@Ahaan - +1 for the answer. Nonetheless, a good teacher, at any level, should have no trouble realizing that your three radical expressions represent the same number. However, having said that, and being a US resident, maybe not.
Dec
29
awarded  Nice Answer
Dec
22
answered Removable discontinuity question
Oct
29
awarded  Yearling
Sep
27
answered Finding a basis for a subspace in $\;\Bbb R^4\;$
Sep
11
comment Cant understand some definitions of abstract algebra, can you help me please?
I don't know the reason for the term "over", but it is used to indicate the field from which the scalars for the scalar multiplication are chosen. In a similar vein, if one talks about the finite dimensional space $F^n$, then one considers this space as being "over $F$" in the sense that the $n$-tuples have entries that come from $F$.
Aug
31
comment A Book for abstract Algebra
I'm currently using Pinter's book in my abstract algebra course because it is well-written, inexpensive, and has great exercise sets that break sometimes difficult discussions into manageable pieces.
Aug
24
comment Does every group have a 'cyclization'?
@Alexander - It certainly seems every group has a trivial one, which is why I don't think the trivial case is very interesting. I'm kind of distracted by other obligations at the moment, but it seems that $\mathbb{Z}$ has both itself and the trivial group as cyclizations.
Aug
24
comment Does every group have a 'cyclization'?
It might make a better question to ask what groups have nontrivial cyclizations, since not all have non-trivial ones.