407 reputation
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bio website hitono.info
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visits member for 1 year, 10 months
seen 2 days ago

Dec
9
awarded  Caucus
Jul
2
awarded  Curious
Apr
21
comment If there are obvious things, why should we prove them?
Elitist much? I wonder how many grossly underpaid but otherwise mathematically apt people are down at walmart right now. (Including adjunct math faculty, even!)
Apr
18
comment Proving that the maximum of two convex functions is also convex
Does this apply similarly for the maximum of two concave functions?
Apr
18
accepted Is a continuously differentiable function convex if all its partial second derivatives are non-negative?
Apr
9
comment Pizza theorem with realistic extension
The proof sketch you gave requires that the crust be separable from the pizza, though.
Apr
3
comment Can a coin with an unknown bias be treated as fair?
This is one of my favorite questions from Cover and Joy's info theory text book :)
Feb
13
comment Why are the rational numbers not continuous?
I sort of get it from the wikipedia article: "An example of a set that lacks the least-upper-bound property is ℚ, the set of rational numbers. Let S be the set of all rational numbers q such that $q^2 < 2$. Then S has an upper bound but no least upper bound in ℚ: If we suppose p ∈ ℚ is the least upper bound, a contradiction is immediately deduced because between any two reals x and y (including √2 and p) there exists some rational p', which itself would have to be the least upper bound (if p > √2) or a member of S greater than p (if p < √2)."
Feb
13
comment Why are the rational numbers not continuous?
one more question: when you say, "You've so just obtained ℝ!" here, does your argument assert that $\mathbb{Q}$ does not contain non-empty bounded above sets with a least upper bound? I'm having trouble understanding why not. Couldn't you just choose the largest element of a set contained in $\mathbb{Q}$ as its upper bound? I guess I'm really asking what situation yields a supremum not in $\mathbb{Q}$ but in $\mathbb{R}$.
Feb
12
comment Why are the rational numbers not continuous?
Can you state briefly what the Archimedian property exactly is for completeness' sake?
Feb
9
comment Find integral when $dx$ is in the numerator
So sick of that "non-standard" term tacked on to this significantly more intuitive interpretation.
Feb
3
comment What's a good class of functions for bounding/comparing ratios of complicated logarithms?
That's a good one. Closer to home for me is visual/auditory senses, which give you great sensitivity at low ranges without causing a seizure when a truck passes :)
Feb
3
comment What's a good class of functions for bounding/comparing ratios of complicated logarithms?
Geez, I should have seen that. My head was still spinning from the amount of algebra it took to get everything else out of the way. Thanks.
Feb
3
accepted What's a good class of functions for bounding/comparing ratios of complicated logarithms?
Feb
3
asked What's a good class of functions for bounding/comparing ratios of complicated logarithms?
Feb
2
revised I'm a teenager hoping to become a mathematician, but math isn't my forte. Is it possible?
Removed erroneous accent mark on forte (the accented one is an unrelated musical term)
Feb
1
comment which exact integration techniques belong in a first year calculus/analysis course?
For signal processing, partial fraction decomposition is definitely the go-to method since most involved systems are composed of functions that can be designed or described that way. I learned that in an engineering class though, after having my brains scrambled by a high-variance distribution of math professors ;)
Jan
30
awarded  Yearling
Jan
21
comment How do I convince my students that the choice of variable of integration is irrelevant?
oh, this answer is good and gets right to the heart (one of the hearts) of the problem. Also good for elucidating CDFs like $F(x) = \int \limits^{x}_0 f(z) dz$
Jan
21
revised Pizza theorem with realistic extension
added more surmising