Mark Eichenlaub
Reputation
3,254
Next privilege 5,000 Rep.
Approve tag wiki edits
 Mar10 answered Why Circle encloses largest Area? Mar5 comment Good Physical Demonstrations of Abstract Mathematics Here's a blog post I wrote a while ago about proving Vieta's formula with basic physics: arcsecond.wordpress.com/2010/09/17/… Feb24 accepted Why is Euclidean geometry scale-invariant? Feb23 comment Prove that Honeycomb Structures are the Most Geometrically Efficient Structure not really physics that I can tell. probably belongs in math.stackexchange Feb23 awarded Commentator Feb22 awarded Nice Question Feb21 comment Why is Euclidean geometry scale-invariant? Interesting point. Then all I need to do is understand how why the Pythagorean theorem is special to Euclidean geometry. The most famous proofs that pop to mind for me involve things like similar triangles, though, and so using them would be circular reasoning. Feb21 comment Why is Euclidean geometry scale-invariant? @Qiaochu I know some linear algebra and a little abstract algebra from studying physics, so yes a more modern treatment would be interesting, but depending on what tools it uses I might need a reference to understand the background. Feb21 asked Why is Euclidean geometry scale-invariant? Feb21 awarded Editor Feb21 revised How to find the distance between a point and line joining two points on a sphere? changed "C" to "X" to fit with picture Feb21 suggested approved edit on How to find the distance between a point and line joining two points on a sphere? Feb17 comment Derivation of Fourier Series? This isn't really a physics question. I'll flag for the mods to migrate it to math.stackexchange. Feb3 accepted How many ways can $r$ nonconsecutive integers be chosen from the first $n$ integers? Feb3 comment How many ways can $r$ nonconsecutive integers be chosen from the first $n$ integers? @wok, @Moron Thank you for the links. I saw that post before asking the question, but once I realized it was answering a slightly different question, I didn't read it in detail. I guess I should have. Feb3 comment How many ways can $r$ nonconsecutive integers be chosen from the first $n$ integers? Yes, I get in now. The answer is just ${}_{n-r+1}C_r$. Thank you encouraging me rather than giving it away. Feb2 comment How many ways can $r$ nonconsecutive integers be chosen from the first $n$ integers? Nice and simple. Thank you. Feb2 comment How many ways can $r$ nonconsecutive integers be chosen from the first $n$ integers? @Moron Yes, I did search this site. I found someone talking about non-consecutive birthdays, but that's sampling with replacement, and this is without replacement. Did I miss something? Feb2 asked How many ways can $r$ nonconsecutive integers be chosen from the first $n$ integers? Jan24 accepted Why isn't the gamma function defined so that $\Gamma(n) = n!$?