Peter Luthy
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 Jun 14 answered Why do we care about $L^p$ spaces besides $p = 1$, $p = 2$, and $p = \infty$? Jun 12 comment Weighted Hardy Inequality for bounded domains At least in the case where the function is zero at L, I suppose you've tried the change of variable x to v/(v+1), so that one can attempt to use the inequality in your link (after some algebra) and then do some more algebra to simplify things a bit? It seems like that would work to at least give you some control over the function u(x)-u(L). Would this be at all helpful for your purposes? Why do you need such an inequality? Jun 7 comment What are your experiences of handouts in mathematics lectures? Are you not free to disallow the use of laptops in class? Jun 7 comment What are your experiences of handouts in mathematics lectures? I completely agree with these sentiments, Terry. Such a system is extremely rewarding to students who work hard. Students all have varying levels of raw ability; the only thing you can do as an instructor is make hard work as valuable to them as possible. Jun 7 comment Real analysis has no applications? Greg, I completely agree with you regarding BC calculus. I took BC calculus in high school, and it was a wonderful experience. We did avoid some of the more rigorous details --- I think delta-epsilon proofs of continuity were completely absent, for instance --- but I think I still came out of that course with a great understanding of analysis. I clearly understood the delicate interplay between approximation and error terms. Once deltas and epsilons came, I needed only understand the framework; the tools were already there. May 19 comment Why is Lebesgue integration taught using positive and negative parts of functions? Fatou's lemma is pretty useful. May 16 awarded Commentator May 16 comment Differentiable structures on R^3 The inverse of $x^3$ is not smooth, but the term diffeomorphism as it pertains to differentiable structures does not require this: a bijective map $f:\mathbb{R}\rightarrow\mathbb{R}$ is a diffeomorphism of $(\mathbb{R},A)$ and $(\mathbbf{R},B)$ if $x\in A$ iff $x(f)\in B$. Here A and B are maximal atlases. May 15 comment Beginning a sentence with a mathematical symbol Greg, do you have any particular examples worth sharing, or are you simply finding your prose has become a monotonous glob of ideas punctuated by thus and therefore? May 15 answered Beginning a sentence with a mathematical symbol May 15 comment If ErdÅ‘s is published as Erdös in a paper, which do I cite? The definitive answer to "are there good math jokes?" May 13 answered Would Euler's proofs get published in a modern math Journal, especially considering his treatment of the Infinite? May 11 comment Evaluation of the following Series Gerald, Max wrote the incorrect general term, hence my error. $\displaystyle{\sum_{n=1}^\infty\frac{1}{((2n-1)2n)^2}=\sum_{n=1}^\infty\frac{1}‌​{(2n-1)^2}-2\sum_{n=1}^\infty\frac{1}{((2n-1)2n)^2}+\sum_{n=1}^\infty\frac{1}{(2n‌​)^2}}$. The first and second sums add to give $\displaystyle{\sum_{n=1}^\infty\frac{1}{n^2}}$, which then gives Michael Greenblatt's result. May 11 comment Evaluation of the following Series Ah, I see, you have written the general term down incorrectly, Max. It is not $1/(n(n+1))^2$ . It should be $1/(2n(2n-1))^2$. May 11 comment Evaluation of the following Series The second sum which you have written does not sum to $\log 2$. It is an alternating series which sums to 1. May 11 comment Evaluation of the following Series haha I had just written this up a second before the site indicated you posted your solution... here is what I wrote: Write $\frac{1}{n^2(n+1)^2}=\left(\frac{1}{n}-\frac{1}{n+1}\right)^2=\frac{1}{n^2}-\fr‌​ac{2}{n(n+1)}+\frac{1}{(n+1)^2}$. Summing the first term gives $\pi^2/6$, the last term gives $-1+\pi^2/6$, and the middle term is an alternating seriesgives $-2$, so that the whole sum is $\frac{\pi^2}{3}-3$. May 5 answered What are trig classes like within a universe that's “noticeably” hyperbolic? May 4 comment How did Gauss discover the invariant density for the Gauss map? You're very welcome! May 3 answered How did Gauss discover the invariant density for the Gauss map? May 1 awarded Supporter