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15h
revised Introduction to Filters in Topology
minor typo; edited tags
16h
revised Why is $f(x) = x^2$ uniformly continuous on [0,1] but not $\mathbb{R}$
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1d
revised Hahn-Banach Theorem for separable spaces without Zorn's Lemma
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1d
comment Hahn-Banach Theorem for separable spaces without Zorn's Lemma
BTW I consider adding full reference much more useful than just saying "in the book I'm reading".
1d
revised Hahn-Banach Theorem for separable spaces without Zorn's Lemma
edited body
1d
revised Hahn-Banach Theorem for separable spaces without Zorn's Lemma
added 20 characters in body
1d
comment Linear Algebra: determine whether the sets span the same subspace
I had similar experience, that some students simply put vectors into matrix as rows (or columns) and row reduce without really knowing what they are doing. However, I think that this is exactly the type of problem, where finding rref seems to me rather efficient way to solve it.
1d
answered Linear Algebra: determine whether the sets span the same subspace
1d
revised Finding a differentiable function satisfying some given conditions
added 87 characters in body; edited tags
1d
revised Finding whether a vector is in the span of a set of vectors
added 2 characters in body
1d
revised Relations between cluster points of nets and types of accumulation points of sets
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1d
revised can't determine the convergence/divergence here
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1d
comment can't determine the convergence/divergence here
@Abomm Another way to see that $t_n$ converges to zero is to notice that $1/\sqrt n\to 0$. Then the same is true for the averages: math.stackexchange.com/questions/207910/…
1d
revised Finding whether a vector is in the span of a set of vectors
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1d
revised Finding whether a vector is in the span of a set of vectors
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1d
answered Finding whether a vector is in the span of a set of vectors
1d
revised Finding whether a vector is in the span of a set of vectors
This is not a question about Schauder basis; edited tags
2d
revised Show that the series is not absolutely convergent but is uniformly convergent in the whole complex plane
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2d
revised Show that $\frac{1}{1+k}=\frac{\frac{1}{k}}{1+\frac{1}{k}}\leq \ln(1+\frac{1}{k})\leq\frac{1}{k}$
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2d
comment If $\lim_{n \rightarrow \infty} a_n=L$ then $\lim_{n \rightarrow \infty} f(a_n)=f(L)$?
@JellyBelly Perhaps it is worth adding caveat that from this we can calculate the limit $L$, assuming the sequence converges. Although in this particular case, for the function $f(x)=1+\sqrt x$, this sequence will converge for any choice of $a_1$. But, for example, if you look at $f(x)=x^2$ and $a_1=2$, then the sequence given by $a_{n+1}=f(a_n)$ clearly does not converge neither to $0$ nor to $1$, which are the only solutions of $f(x)=x$.