Ben Alpert
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 Feb26 awarded Citizen Patrol Feb17 comment Proving the value of a limit using the $\epsilon$-$\delta$ definition I don't think your sarcastic condescension helps anyone. Feb13 revised Finding $\int_0^{\pi/2} \sin x\,dx$ deleted 39 characters in body Feb13 comment Finding $\int_0^{\pi/2} \sin x\,dx$ @Arturo: Yes, but why is the derivative of $\cos(x)$ equal to $-\sin(x)$ when $x$ is measured in radians? Feb13 comment Finding $\int_0^{\pi/2} \sin x\,dx$ @Isaac, you're right that that does make more sense. I'll change my question (though I'm not sure it was particularly unclear originally). Feb13 comment Finding $\int_0^{\pi/2} \sin x\,dx$ So you answered why the integrals give different answers scaled by a the ratio between a degree and a radian, but I already knew this. My question was why radians are special and give the answer of 1 (which you skip entirely when you say, "We know that…"). Sorry if my question was unclear. Feb13 asked Finding $\int_0^{\pi/2} \sin x\,dx$ Feb13 accepted Coloring points on an n-gon Feb13 comment Coloring points on an n-gon Perfect, exactly what I was looking for! Feb13 comment Coloring points on an n-gon Thanks; I'm accepting Qiaochu's answer because it's more complete (and also was a few seconds before yours). Feb13 asked Coloring points on an n-gon Jan26 comment I want to put my words into a formula/algorithm but I lack the mathematical fortitude I agree with Yuval here; there's no reason to use any fancy math notation because the words you have currently are already very clear. Adding any symbols would unnecessarily complicate the algorithm. (And anyway, I don't think that there is any standard notation for what you want. Probably the best you can do is just write pseudocode for the algorithm, but that's not particularly mathy.) Jan24 comment Algorithm for generating integer partitions @Will: Are you sure? I think that should work fine; that's what maxval is for. Jan22 comment a question related to two competing patterns in coin tossing @PEV: I can't tell if I'm just being really stupid here, but I'm still unsure how that helps. For example, if with a fair coin you're looking for TH vs HH, it's much more likely ($3/4$ vs. $1/4$) that you'll see TH first because once you see a single T, it's impossible to get HH before seeing TH. How do we get the same answer using your method? (Presumably that would be $pq$ vs $p^2$.) Jan22 comment a question related to two competing patterns in coin tossing @PEV: So if that's a fair coin, you're saying the probability is $1/32$. Of course, that's the probability that a random flip sequence of length 5 is equal to HTHTH but doesn't seem to answer whether HTHTH or HTHH is more likely to appear first. Jan22 comment a question related to two competing patterns in coin tossing Sorry, but does this actually answer either of the part of the problem? I'm (not very familiar with Markov chains and am) confused about what the mean time tells you. (And I'm assuming $q = 1 - p$; is that right?) Jan22 comment a question related to two competing patterns in coin tossing I'm also interested to know how to solve this problem; I've seen variations a few times on contests but never knew how to solve it. Dec11 awarded Quorum Nov16 awarded Enlightened Nov16 awarded Nice Answer