Huy

1,704 reputation

619

bio	website	anhhuy.ch
	location	Switzerland
	age	20
visits	member for	2 years, 6 months
	seen	May 18 at 13:00
stats	profile views	257

My name is Anh Huy Truong and I am currently studying mathematics at the ETH Zürich.

	1,704 reputation	bio	website	anhhuy.ch	visits	member for	2 years, 6 months
619 badges		location	Switzerland		seen	May 18 at 13:00

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66 Questions

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kviews

Anecdotes about famous mathematicians or physicists

math-history

mar 23 at 21:04 P.. 8,905

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292

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What is the volume of $\{ (x,y,z) \in \mathbb{R}^3_{\geq 0} |\; \sqrt{x} + \sqrt{y} + \sqrt{z} \leq 1 \}$?

may 1 '11 at 8:36 Christian Blatter 32.6k

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660

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A simple way to evaluate $\int_{-a}^a \frac{x^2}{x^4+1} \, \mathrm dx$?

homework analysis integral

may 6 '11 at 17:06 J. M. 38.9k

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550

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How to prove $\lim_{n \to \infty} \sqrt{n}(\sqrt[n]{n} - 1) = 0$?

calculus limit

oct 17 '11 at 19:17 Srivatsan 15.6k

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kviews

A program to draw simple geometry (points, lines, dotted lines etc.)

geometry math-software

jun 12 '12 at 15:57 MJD 21k

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660

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How to prove $C_1 \|x\|_\infty \leq \|x\| \leq C_2 \|x\|_\infty$?

homework real-analysis vector-spaces norm

jan 7 '12 at 3:03 Srivatsan 15.6k

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226

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For which $p \in \mathbb{R}_{>0}$ does the integral $\int_{[0,1]^n} \frac{\mathrm dx}{(x_1^p+2x_2^p + … + nx_n^p)^{1/3}}$ converge?

homework analysis integral

may 10 '11 at 1:53 Luke 916

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answers

206

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How to prove $\max_{x \in I} |f(x)| \leq \max_{x \in I} |f'(x)|$?

analysis

feb 21 '11 at 13:19 Did 103k

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658

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How to prove that a torus has the same volume as a cylinder (with the height equal to the torus' perimeter)

geometry

nov 24 '10 at 20:37 Pelli 156

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151

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Is there a vector space that cannot be an inner product space?

linear-algebra

nov 30 at 9:16 Christian Blatter 32.6k

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243

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Lack of understanding of the proof of the existence of an irreducible polynomial of any degree $n \geq 2$ in $\mathbb{Z}_p[x]$

finite-fields

mar 30 '12 at 12:46 Jyrki Lahtonen 30.9k

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200

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Prove by induction that for all $n \geq 3$: $n^{n+1} > (n+1)^n$

induction

jan 8 '12 at 16:49 rtybase 68

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356

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The Tuesday Birthday Problem - why does the probability change when the father specifies the birthday of a son?

probability

dec 1 '11 at 17:54 Brian M. Scott 155k

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167

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Is $f(x) = \sum_{n=-\infty}^\infty \frac{2^n \log x}{1+(2^n \log x)^2}$ for $x \geq 2$ constant?

calculus

nov 22 '11 at 16:37 Phira 12.2k

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354

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What does $(m, n) = 1$ mean?

notation

mar 14 '11 at 17:33 Community♦ 1

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166

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How to prove the error estimate of the Newton-iteration?

analysis numerical-methods

dec 14 '10 at 19:52 Huy 1,704

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119

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Given a number $11 \leqslant n\leqslant 99$, how to write a couple of numbers which total to $n$

puzzle magic-square

jul 20 at 15:17 The Chaz 2.0 4,854

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177

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How to prove $\sum\limits_{n=p+1}^\infty \frac1{n^2-p^2} = \frac1{2p} (1+\frac12 + \cdots + \frac1{2p})$ for all $p \in \mathbb N$?

sequences-and-series

may 31 '12 at 16:22 Chris's wise sister 11.5k

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answer

107

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How to show $\langle a, b \; | \; aba = bab \rangle \cong \langle x,y \; | \; x^3=y^2 \rangle$? [duplicate]

group-theory

mar 6 '12 at 13:41 Jyrki Lahtonen 30.9k

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265

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What do I know when the curl of a vector field equals 0?

homework analysis

may 15 '11 at 17:48 t.b. 43.2k

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967

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How to use the Lagrange's remainder to prove that log(1+x) = sum(…)?

analysis taylor-expansion power-series

dec 10 '10 at 17:00 Robert Pollack 21

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595

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Calculate the surface area of a solid of revolution

calculus

dec 5 '10 at 0:38 J. M. 38.9k

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282

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Stuck at the proof of the existence of the partial fraction expansion

analysis

nov 28 '10 at 19:55 Community♦ 1

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answer

155

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How do I do “calculations” with tensors?

tensor-products tensors

jun 19 '12 at 14:51 rschwieb 21k

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365

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Domain of the Gamma function

analysis special-functions gamma-function

apr 17 '12 at 1:31 J. M. 38.9k

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494

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Which sequences converge in a cofinite topology and what is their limit?

general-topology

nov 6 '11 at 22:08 Huy 1,704

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101

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How to derive the limits of $\sum_{k=0}^\infty k q^k$ and $\sum_{k=0}^\infty k^2 q^k$ for $|q| < 1$ without using differentiation/integration?

calculus sequences-and-series

oct 23 '11 at 16:23 tkr 410

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answer

658

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Stuck at the proof of the Riemann-Lebesgue lemma

homework analysis integral

may 1 '11 at 14:52 Huy 1,704

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277

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Why is $z = x+iy \mapsto x$ not differentiable in $0 \in \mathbb{C}$?

complex-analysis

apr 11 '11 at 20:49 yoyo 4,850

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answer

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How can I find $n$ such that $\sum_{k=1}^n f(k) \leq c$ without computing many partial sums?

calculus sequences-and-series

nov 9 at 3:19 Greg Ros 599