User Huy - Mathematics Stack Exchange

bio	website	anhhuy.ch
	location	Switzerland
	age	20
visits	member for	2 years, 6 months
	seen	yesterday
stats	profile views	257

	1,704 reputation	bio	website	anhhuy.ch	visits	member for	2 years, 6 months
619 badges		location	Switzerland		seen	yesterday

147

373

votes

25

answers

24

kviews

Can I use my powers for good?

soft-question career-development

apr 11 at 0:40 MGA 70

136

188

votes

21

answers

17

kviews

How to study math to really understand it and have a healthy lifestyle with free time?

soft-question advice

dec 31 at 5:24 Grigor 1

81

131

votes

9

answers

8

kviews

What's an intuitive way to think about the determinant?

linear-algebra intuition determinant

may 13 at 7:14 MJD 20.6k

27

121

votes

2

answers

12

kviews

Proving you can't make $2011$ out of $1,2,3,4$: nice twist on the usual

number-theory elementary-number-theory recreational-mathematics

jan 3 '12 at 16:17 David Bevan 2,805

24

86

votes

3

answers

3

kviews

Is 2048 the highest power of 2 with all even digits (base ten)?

number-theory powers

dec 8 at 6:43 Cameron Buie 27.2k

25

52

votes

3

answers

2

kviews

Is there an integral that proves $\pi > 333/106$?

calculus real-analysis integral approximation pi

feb 25 at 15:59 Michael Hardy 47.7k

15

49

votes

1

answer

4

kviews

Why are rings called rings?

abstract-algebra terminology math-history

sep 3 '11 at 8:35 t.b. 43.1k

13

48

votes

3

answers

1

kviews

How did Hermite calculate $e^{\pi\sqrt{163}}$ in 1859?

real-analysis math-history

jan 26 '12 at 3:52 J. M. 38.9k

21

46

votes

8

answers

8

kviews

What is the importance of the Collatz conjecture?

number-theory soft-question collatz

mar 8 at 14:29 Arthur Fischer 21.2k

9

40

votes

3

answers

1

kviews

Volumes of n-balls: what is so special about n=5?

geometry

2d ago wendy.krieger 242

15

40

votes

8

answers

2

kviews

Are the “proofs by contradiction” weaker than other proofs?

logic proof-theory

oct 18 at 16:54 Noah Snyder 4,296

13

37

votes

3

answers

1

kviews

How come the number $N!$ can terminate in exactly $1,2,3,4,$ or $6$ zeroes but never $5$ zeroes?

elementary-number-theory factorial

may 5 '12 at 17:07 Aryabhata 47.4k

7

34

votes

3

answers

839

views

Putting many disks in the unit square

geometry combinatorics packing-problem

sep 11 '11 at 21:05 joriki 92.1k

15

30

votes

2

answers

3

kviews

Mathematical explanation behind a picture posted (lifted from facebook)

image-processing

aug 7 at 21:25 Community♦ 1

20

28

votes

13

answers

4

kviews

Anecdotes about famous mathematicians or physicists

math-history

mar 23 at 21:04 P.. 8,850

16

28

votes

2

answers

897

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Evaluating $\int P(\sin x, \cos x) \text{d}x$

calculus integral faq

apr 19 '12 at 21:47 Qiaochu Yuan 117k

27

24

votes

4

answers

3

kviews

Connection between fourier transform and taylor series

intuition fourier-analysis taylor-expansion integral-transforms

mar 19 '11 at 8:49 Christian Blatter 32.3k

18

23

votes

28

answers

2

kviews

Classical texts that should not be missing from any shelf

reference-request soft-question big-list

jan 15 '12 at 15:08 Zach Langley 605

8

23

votes

3

answers

1

kviews

What is the value of $1^i$?

complex-numbers exponentiation powers

nov 24 '11 at 13:08 Ilmari Karonen 8,226

5

23

votes

1

answer

448

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Smooth functions for which $f(x)$ is rational if and only if $x$ is rational

number-theory real-analysis

dec 10 '10 at 19:26 J. J. 2,576

9

21

votes

6

answers

1

kviews

Proving : $ \bigl(1+\frac{1}{n+1}\bigr)^{n+1} \gt (1+\frac{1}{n})^{n} $

algebra-precalculus inequality

oct 21 at 14:18 robjohn♦ 59.1k

17

21

votes

2

answers

2

kviews

What do eigenvalues have to do with pictures?

linear-algebra eigenvalues eigenvectors image-processing

52m ago J. M. 38.9k

7

21

votes

8

answers

1

kviews

What's so special about sine? (Concerning $y'' = -y$)

differential-equations

mar 6 '12 at 23:35 Anixx 968

14

20

votes

15

answers

2

kviews

Useful examples of pathological functions

soft-question big-list calculus real-analysis

mar 5 '12 at 12:00 draks ... 6,308

7

20

votes

4

answers

772

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Is the integral $\int_0^\infty \frac{\mathrm{d} x}{(1+x^2)(1+x^a)}$ equal for all $a \neq 0$?

calculus integral definite-integral

dec 6 '11 at 4:44 Michael Hardy 47.7k

6

20

votes

3

answers

884

views

tough integral involving $\sin(x^2)$ and $\sinh^2 (x)$

calculus integral improper-integrals

nov 22 at 23:07 Argon 9,223

7

20

votes

4

answers

735

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Math behind rotation in MS Paint

rotations

jun 24 '11 at 9:49 Samuel 2,287

7

19

votes

2

answers

545

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How to prove that $\sum\limits_{n=1}^\infty\frac{(n-1)!}{n\prod\limits_{i=1}^n(a+i)}=\sum\limits_{k=1}^\infty \frac{1}{(a+k)^2}$ for $a>-1$?

real-analysis sequences-and-series convergence

dec 30 at 8:22 UnkleRhaukus 601

9

17

votes

6

answers

1

kviews

$f\colon\mathbb{R}\to\mathbb{R}$ such that $f(x)+f(f(x))=x^2$ for all $x$?

real-analysis functional-equations

dec 7 '11 at 0:19 Community♦ 1

6

16

votes

1

answer

1

kviews

New Year's eve riddle

puzzle

apr 20 '12 at 12:40 Ekuurh 122

Huy

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