Reputation
12,743
Top tag
Next privilege 15,000 Rep.
Protect questions
Badges
4 30 78
Newest
 Yearling
Impact
~363k people reached

Feb
1
answered How do we conclude that $f(x)=0, \forall x\in \mathbb{R}$ ?
Dec
18
answered How to show that $Sp\{u+v-3w,2v-w,t+w,v+w\} = Sp\{u,v,w,t\}$
Dec
16
awarded  Yearling
Nov
18
awarded  Popular Question
Nov
18
comment When data mining, how to solve the problem that the positive instances are much less than negative instances in dataset?
You can find a lot of information Googling about skewed classes and logistical regression
Nov
18
comment When data mining, how to solve the problem that the positive instances are much less than negative instances in dataset?
stats.stackexchange.com/questions/6067/…
Nov
9
accepted Proving that the maximal abelian extension contains all abelian extensions
Nov
9
answered Prove the infinite union is not regular
Nov
7
comment An exercise related to Krull topology - showing that two bases define the same topology
@random123 - Could please you add some details ?
Nov
7
asked An exercise related to Krull topology - showing that two bases define the same topology
Nov
6
accepted What is a good theoretical, yet somewhat practical, book about error correction codes?
Nov
6
accepted Subgroups of Index $2$ of $(\mathbb{Z}_{2})^{\aleph_{0}}$
Nov
6
comment Subgroups of Index $2$ of $(\mathbb{Z}_{2})^{\aleph_{0}}$
@AsafKaragila - I mean the one group, up to isomorphism, of order $2$. I don't know about the dyadic integers (yet ?)
Nov
6
revised Subgroups of Index $2$ of $(\mathbb{Z}_{2})^{\aleph_{0}}$
added 104 characters in body
Nov
6
asked Subgroups of Index $2$ of $(\mathbb{Z}_{2})^{\aleph_{0}}$
Nov
6
answered Prove that the Language $L= \{ 0^n1^m \;|\; n,m \ge 0 \}$ is regular
Nov
3
awarded  Enlightened
Nov
3
awarded  Nice Answer
Nov
2
comment Checking irreducibility of a polynomial in $\mathbb{K}[x,y]$ and PAC fields
Thank you for posting an answer, I think there is a counter example for your claim: Take $K=\mathbb{R}$ and $\phi=-x^{2}$ which is separable as every irreducible factor is separable. $n=2$ and the $n$-th roots of unity are $\pm1\in\mathbb{R}$. $F(x,y)=y^{2}-\phi(x)=y^{2}+x^{2}=(y+ix)(y-ix)$ is a factorization over $\mathbb{C}$ so that $F(x,y)$ is not irreducible as claimed. Did I miss something ?
Nov
2
asked Proving that $Gal(K^{\text{sep}}/K)=Aut_{K}(\tilde{K})$