User Theta30 - Mathematics Stack Exchange

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	age	36
visits	member for	2 years, 3 months
	seen	May 13 at 20:30
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	419 reputation	bio	website		visits	member for	2 years, 3 months
315 badges		location	Canada		seen	May 13 at 20:30

16

39

votes

7

answers

2

kviews

Could I be using proof by contradiction too much?

proof-writing contradiction

mar 7 at 20:49 Joseph 1,926

34

36

votes

14

answers

5

kviews

Solving the integral $\int_{0}^{\infty} \frac{\sin{x}}{x} \ dx = \frac{\pi}{2}$?

analysis complex-analysis

mar 12 at 13:08 xpaul 1,056

23

33

votes

4

answers

3

kviews

Is there a quick proof as to why the vector space of $\mathbb{R}$ over $\mathbb{Q}$ is infinite-dimensional?

linear-algebra

sep 26 '11 at 20:12 Leon Lampret 2,630

22

23

votes

4

answers

1

kviews

Understanding the intuition behind math

intuition math-history

feb 27 '11 at 6:40 Vicfred 726

6

23

votes

5

answers

2

kviews

What is an intuitive explanation for $\operatorname{div} \operatorname{curl} F = 0$?

multivariable-calculus intuition

dec 28 '11 at 3:17 Srivatsan 15.6k

5

22

votes

2

answers

492

views

Can we make $\tan(x)$ arbitrarily close to an integer when $x\in \mathbb{Z}$?

calculus real-analysis

mar 2 '11 at 7:05 Pete L. Clark 44.7k

6

21

votes

6

answers

528

views

Does exceptionalism persist as sample size gets large?

probability statistics

nov 30 at 0:41 Mike Spivey 25.9k

6

17

votes

4

answers

518

views

What am I doing when I separate the variables of a differential equation?

calculus differential-equations

mar 17 '11 at 9:41 Christian Blatter 32.7k

4

16

votes

3

answers

503

views

How can I sum the infinite series $\frac{1}{5} - \frac{1\cdot4}{5\cdot10} + \frac{1\cdot4\cdot7}{5\cdot10\cdot15} - \cdots\qquad$

calculus sequences-and-series analysis

dec 18 '11 at 13:02 Eric 33.3k

9

14

votes

2

answers

929

views

Sum of reciprocals of numbers with certain terms omitted

sequences-and-series

mar 13 at 23:27 robjohn♦ 60k

12

14

votes

5

answers

1

kviews

Please show $\int_0^\infty x^{2n} e^{-x^2}\mathrm dx=\frac{(2n)!}{2^{2n}n!}\frac{\sqrt{\pi}}{2}$ without gamma function?

calculus analysis integral

oct 21 at 18:20 Chris's wise sister 11.5k

5

11

votes

2

answers

948

views

Physicists, not mathematicians, can multiply both sides with $dx$ - why?

calculus analysis physics

jun 23 '11 at 9:58 miracle173 840

2

10

votes

2

answers

363

views

Integrating $\frac{x^k }{1+\cosh(x)}$

calculus integral special-functions riemann-zeta

mar 25 '12 at 17:26 Peter Tamaroff 26.1k

2

10

votes

1

answer

238

views

How to determine all valuations of the field $\mathbb{Q(\sqrt[n]{2})}$?

algebraic-number-theory absolute-value

jan 21 '12 at 16:22 franz lemmermeyer 1,499

1

9

votes

3

answers

170

views

Integral calculation help

homework integral

jun 15 '11 at 9:17 Shai Covo 17k

1

8

votes

1

answer

505

views

Bell numbers and moments of the Poisson distribution

combinatorics probability

aug 3 at 6:38 joriki 92.8k

2

7

votes

4

answers

1

kviews

Questions on atoms of a measure

measure-theory probability-theory

may 18 at 13:18 Luiz Henrique 11

2

6

votes

5

answers

986

views

Applications of the wreath product?

group-theory

jul 26 '11 at 20:22 Pete L. Clark 44.7k

1

6

votes

3

answers

489

views

An interesting series

real-analysis sequences-and-series

oct 3 '10 at 23:13 Aryabhata 47.7k

2

5

votes

2

answers

361

views

convergence of the maximum of a series of identically distributed variables

homework measure-theory

mar 18 '11 at 6:48 Did 103k

3

5

votes

2

answers

401

views

Fubini's theorem problem

homework real-analysis

mar 10 '11 at 23:14 Viktor 126

8

5

votes

4

answers

558

views

Favorite Math Competition Problems

contest-math

jun 16 '11 at 0:57 ncmathsadist 17.2k

1

5

votes

2

answers

395

views

deadline in math jobs application

soft-question

dec 7 '10 at 7:10 math postdoc 126

1

5

votes

1

answer

113

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Example of Boolean Algebra that satisfies distributive law but violates complete distributive law

boolean-algebra

jan 20 at 15:47 Asaf Karagila 91.6k

1

4

votes

2

answers

173

views

Simpler proof - Non atomic measures

measure-theory set-theory

jan 13 at 11:59 Anonymous 296

4

votes

2

answers

998

views

Evaluating the contour integral $\int_{0}^{\infty}\frac{\sin^{3}(x)}{x^{3}}\mathrm dx$

integral complex-analysis

dec 4 '11 at 14:22 kahen 8,064

3

4

votes

7

answers

918

views

Proving ${n \choose p} \equiv \Bigl[\frac{n}{p}\Bigr] \ (\text{mod} \ p)$

number-theory

mar 31 '11 at 7:00 Amir Hossein 1,315

1

4

votes

2

answers

200

views

The Poisson Distribution

calculus stochastic-processes probability-distributions

jul 30 at 19:56 Norbert 20.7k

3

votes

1

answer

354

views

How to use Maple derive the 4th central moment for this distribution?

probability maple

mar 3 '11 at 21:06 Did 103k

1

3

votes

4

answers

5

kviews

Finding the limit when denominator = 0

calculus limit

may 16 '11 at 3:25 Isaac 21.1k

Theta30

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