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visits member for 2 years, 11 months
seen Dec 13 at 21:51

Nov
10
comment Find a subsheaf of a coherent sheaf, whose quotient is torsion sheaf.
Use induction on $r$.
Oct
30
awarded  Benefactor
Oct
30
accepted Global generation of $\mathcal{O}_{\mathbb{P}(\mathcal{E})}(1)$ and $\mathcal{E}$
Aug
1
comment What are differences between affine space and vector space?
What is it precisely that you need explained?
Jul
2
awarded  Curious
Jun
19
comment Showing holomorphic function is constant via conformal map
en.wikipedia.org/wiki/Joukowsky_transform
Jun
19
asked properties of certain semigroup action on $\mathbb{Z}/p\mathbb{Z}$
May
12
comment Isomorphism between two $K$-algebras
I'd suggest to try without variables: Let $\phi: B \to A$ be ring homomorphism, and $I \subset B$ an ideal. Describe a natural isomorphism $A/I^e \simeq A \otimes_B (B/I)$. Hint is to use right exactness of $A \otimes_B (\cdot)$ on $I \to B \to B/I \to 0$.
May
12
revised How and in what context are polynomials considered equal?
added 910 characters in body
May
12
answered How and in what context are polynomials considered equal?
May
10
comment Exponentiation with a random variable
The question is, what is $P(A)$ when $A$ is random variable? This all makes sense if $A$ is an event instead of random variable -- then $A^c$ is just an opposite event, that is, $\Omega - A$.
May
10
answered Homotopy equivalence between $X/A$ and $X$?
Mar
18
comment How can I prove that $\mathcal{O}_X(-n-1) \simeq \Lambda^n(T_X)^*$?
$\mathcal{O}_X(-n-1)$ only makes sense when $X$ is projective variety, and it also depends on an embedding of $X$ into projective space. Also, in general it's not true. It's only true for the special case $X = \mathbb{P}^n$. To see it, as @EricO.Korman says, you can consider Euler sequence.
Mar
18
comment Liouville's theorem for functions not bounded on an isolated set
What do you mean by "bounded on whole plane except for isolated set of points"? You mean that there exists a discrete subset $D \subseteq \mathbb{C}$ such that your function $f: \mathbb{C} - D \to \mathbb{C}$ is bounded?
Mar
17
revised Partial fraction expansion of $\frac{1}{x(x+1)(x+2)\cdots(x+n)}$
more elementary deriviation
Mar
17
answered Prove the determinant map is a natural transformation
Mar
17
answered Partial fraction expansion of $\frac{1}{x(x+1)(x+2)\cdots(x+n)}$
Mar
11
revised If $A^TA$ is invertible, then $A$'s columns are linearly independent (not necessarily square matrix)
added 84 characters in body
Mar
11
answered If $A^TA$ is invertible, then $A$'s columns are linearly independent (not necessarily square matrix)
Mar
11
answered Nonconstructible Algebraic Numbers