User Jeff - Mathematics Stack Exchange

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	location	New Jersey, USA
	age	46
visits	member for	1 year, 4 months
	seen	May 18 at 19:58
stats	profile views	203

	494 reputation	bio	website		visits	member for	1 year, 4 months
214 badges		location	New Jersey, USA		seen	May 18 at 19:58

108

180

votes

8

answers

15

kviews

Is $dy/dx$ not a ratio?

calculus

mar 14 at 3:35 isomorphismes 845

70

162

votes

13

answers

12

kviews

Is value of $\pi = 4$?

geometry analysis pi fake-proofs

may 21 at 16:03 robjohn♦ 60k

18

73

votes

8

answers

2

kviews

What does $2^x$ really mean when $x$ is not an integer?

algebra-precalculus elementary-number-theory exponentiation

apr 23 '12 at 19:00 Michael Hardy 48.3k

17

42

votes

6

answers

2

kviews

Why are all the interesting constants so small?

soft-question meta-math big-picture

mar 21 '12 at 6:23 Adi Dani 6,007

12

40

votes

7

answers

916

views

Am I too young to learn more advanced math and get a teacher?

soft-question self-learning advice

feb 13 at 18:47 Ron Gordon 26.7k

14

31

votes

11

answers

4

kviews

What is the most elegant proof of the Pythagorean theorem?

geometry big-list algebra-precalculus euclidean-geometry

dec 16 at 13:32 Christian Blatter 32.7k

14

29

votes

2

answers

766

views

Prove $\int_0^1 \left| \frac{f^{''}(x)}{f(x)} \right| dx \geq4$

calculus real-analysis

mar 11 '12 at 4:55 Nick Strehlke 3,107

8

29

votes

7

answers

1

kviews

Is there any geometric way to characterize $e$?

real-analysis algebra-precalculus

oct 11 at 11:50 Emmad Kareem 1,637

7

28

votes

7

answers

3

kviews

I can't do math?

soft-question learning

feb 15 '12 at 17:27 Vitalij Zadneprovskij 228

5

24

votes

7

answers

2

kviews

Do odd imaginary numbers exist?

algebra-precalculus complex-numbers parity

dec 6 at 21:04 Jackson Walters 848

4

22

votes

5

answers

2

kviews

Pythagorean Theorem Proof Without Words (request for words)

geometry

feb 2 '12 at 4:31 Rajesh D 1,270

12

21

votes

17

answers

1

kviews

Mathematical toys?

reference-request big-list popular-math

may 14 '12 at 6:16 user31284 97

4

14

votes

1

answer

707

views

Very simple dice game

probability

jul 5 '11 at 18:47 Elliott 1,674

13

14

votes

5

answers

1

kviews

Math GRE Subject Exam

education advice

mar 31 at 6:19 yiyi 1,978

6

13

votes

6

answers

572

views

Calculate the 146th digit after the decimal point of $ \frac{1}{293} $

elementary-number-theory decimal-expansion

feb 11 '12 at 19:39 Sasha 41.4k

1

13

votes

3

answers

2

kviews

Is $\mathbf{Q}(\sqrt{2}, \sqrt{3}) = \mathbf{Q}(\sqrt{2}+\sqrt{3})$?

abstract-algebra field-theory

jun 11 '12 at 8:27 ding8191 261

5

12

votes

2

answers

804

views

Card doubling paradox

paradox probability-theory

jul 22 '10 at 23:44 Cam 478

6

12

votes

4

answers

1

kviews

If $a | m$ and $(a + 1) | m$, prove $a(a + 1) | m$.

number-theory

jan 25 at 0:45 Austin Mohr 11.7k

23

12

votes

19

answers

7

kviews

Does .99999… = 1?

algebra-precalculus decimal-expansion

may 9 at 13:01 badp 542

9

11

votes

3

answers

615

views

Books to study for Math GRE, self-study, have some time.

reference-request soft-question education

aug 13 at 11:22 Holdsworth88 3,470

4

8

votes

5

answers

2

kviews

What rational number is between these two real numbers?

real-analysis

oct 19 at 15:01 George Frank 131

1

7

votes

3

answers

496

views

Probability that sum of rolling a 6-sided die 10 times is divisible by 10?

probability generating-functions

mar 6 '12 at 22:34 Henry 32.1k

2

7

votes

2

answers

200

views

Hard recursion involving sums

sequences-and-series

mar 12 '12 at 0:50 anon 40.3k

2

7

votes

2

answers

590

views

value of $1+\frac{1}{1+2}+\frac{1}{1+2+3}+\frac{1}{1+2+3+4}+\frac{1}{1+2+3+4+5}+\cdots$?

sequences-and-series

feb 10 '12 at 22:16 Arjang 2,447

2

7

votes

3

answers

454

views

Thought experiment for dice game

probability probability-theory dice

apr 16 '12 at 23:56 Matthew Conroy 3,840

3

6

votes

1

answer

838

views

How do I get good at Math?

calculus soft-question self-learning

apr 3 '12 at 21:42 Community♦ 1

1

6

votes

3

answers

534

views

Can the product $AB$ be computed using only $+, -,$ and reciprocal operators?

puzzle

mar 11 at 0:39 Anonymous 1

1

4

votes

3

answers

338

views

What equity is necessary to offer the doubling cube in Backgammon (dice game)

probability recreational-mathematics dice

apr 14 '12 at 5:57 Matthew Conroy 3,840

3

4

votes

6

answers

524

views

Check my solution to $x^2 + x + 1 > 0$

algebra-precalculus inequality

mar 10 '12 at 13:11 Sebastian Schoennenbeck 578

2

3

votes

3

answers

170

views

Solving a kind of differential equation

differential-equations

jun 1 '12 at 8:26 doraemonpaul 3,072

Jeff

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