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Jun
8
comment A finite set is closed
What is the context? Subsets of $\mathbb R$ with the usual topology/metric? Without context it is impossible to answer your question as in fact in an arbitrary topological space not all finite sets need be closed.
Jun
8
comment What are some results that shook the foundations of one or more fields of mathematics?
I had some mysterious downvoted answers lately. Perhaps a troll?
Jun
8
awarded  Nice Answer
Jun
8
answered Evaluate $\lim_{x\to 1}\frac{\sin(x\pi)}{1-x^2}$ without l'hopital rule
Jun
8
comment Is the algebraic “square root of 2” proof consistent with axioms of algebra?
if you prove $P \wedge \neg P$, then you proved a contradiction. That means your entire logical system is inconsistent, and thus can prove anything (both true and false claims). If such a contradiction is found, it will necessitate reconsidering the axioms and/or the logical deductive system in order to salvage a workable system. Nobody is really worried about such a scenario.
Jun
8
answered What are some results that shook the foundations of one or more fields of mathematics?
Jun
7
answered Is the algebraic “square root of 2” proof consistent with axioms of algebra?
Jun
5
comment Is there a counter-example to this problem on convergence of a bounded, strictly increasing sequence?
thanks @jwalk, I corrected it.
Jun
5
revised Is there a counter-example to this problem on convergence of a bounded, strictly increasing sequence?
edited body
Jun
5
answered Is there a counter-example to this problem on convergence of a bounded, strictly increasing sequence?
Jun
5
comment About the Heine-Cantor theorem.
@bof en.wikipedia.org/wiki/Heine%E2%80%93Cantor_theorem
Jun
5
comment About the Heine-Cantor theorem.
uniformly continuous on which set???
Jun
5
comment About the Heine-Cantor theorem.
what about it??
Jun
5
comment Induction on finite subset of natural numbers
I wonder what the reason for the down vote is.
Jun
5
answered About the Heine-Cantor theorem.
Jun
4
comment Why is $f = x^3$ a homeomorphism when its inverse is undefined for all negative numbers?
$(-8)^{\frac{1}{3}}=-2$ since $(-2)^3=-8$.
Jun
4
answered Given any linear map from basis to a space W, it can be expanded to a linear map from whole space to a space W
Jun
4
answered Induction on finite subset of natural numbers
Jun
4
asked variation on the image of a functor
Jun
3
revised Categories of $n$-ary relations?
deleted 1 character in body