Christoph

Member for 9 years, 10 months
Last seen more than a month ago

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24,384

24.4k
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2020
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Top tag

linear-algebra

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Answers

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Score Activity Newest

46

Is the determinant differentiable?

Apr 23, 2014

38

What is the difference between Cauchy and convergent sequence?

Mar 27, 2014

35

The boundary of an $n$-manifold is an $n-1$-manifold

Nov 6, 2013

20

Calculus: Why do we ignore dx?

Mar 29, 2021

19

What is an additive functor?

Oct 14, 2015

Questions

View all 21 questions

Score Activity Newest Views

22

Rank-nullity theorem for free $\mathbb Z$-modules

Oct 31, 2014

16

Axiomatizing topology through continuous maps

Apr 16, 2014

11

Dual of a rational convex polyhedral cone

Jan 8, 2014

10

The topology on $X/{\sim}\times X/{\sim}$ is not induced by $\pi\times\pi$.

Jun 4, 2014

8

Reconstructing an Affine Variety from its Coordinate Ring

Oct 22, 2013

Tags

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linear-algebra

361

Score

201

posts

abstract-algebra

215

Score

96

posts

general-topology

196

Score

70

posts

real-analysis

174

Score

34

posts

group-theory

165

Score

65

posts

Reputation

+10

Does $\text{rank}(AB)= \text{rank}(BA)= \text{rank}(A)$ imply that B is invertible?

+10

tensor product and matrix multiplication distributive properties

+10

Why is the notation $A\setminus B$ preferred over $A-B$?

+10

The boundary of an $n$-manifold is an $n-1$-manifold

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Refiner

Sep 6, 2018
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Jan 17, 2019
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Sep 10, 2018

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matrices

Nov 11, 2020
general-topology

Aug 9, 2017
group-theory

Feb 16, 2020

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Votes cast

378

upvotes

284

downvotes

265

question votes

397

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