User Timothy Wagner

88 votes

How to show that every Boolean ring is commutative?

answered Nov 14, 2010 at 18:42

75 votes

Accepted

Does $R[x] \cong S[x]$ imply $R \cong S$?

answered Dec 8, 2010 at 13:54

30 votes

Accepted

$I+J=1 \Rightarrow I^n+J^n = 1$ for ideals (or elements in GCD domain) [Freshman's Dream Binomial Theorem]

answered Nov 15, 2010 at 14:40

27 votes

Can $n!$ be a perfect square when $n$ is an integer greater than $1$?

answered Nov 30, 2010 at 22:56

23 votes

Accepted

Intuition behind $dx \wedge dy=-dy \wedge dx$

answered Nov 23, 2010 at 0:11

21 votes

Accepted

Can I learn Calculus on the web, for free, using simple tutorials?

answered Dec 13, 2010 at 15:05

20 votes

Accepted

A Laskerian non-Noetherian ring

answered Dec 14, 2010 at 23:35

20 votes

Limit of the nested radical $\sqrt{7+\sqrt{7+\sqrt{7+\cdots}}}$

answered Nov 26, 2010 at 7:18

19 votes

Accepted

Factorial of a non-integer number

answered Nov 27, 2010 at 20:05

15 votes

deadline in math jobs application

answered Dec 5, 2010 at 3:21

14 votes

Accepted

Algebraic structure cheat sheet anyone?

answered Dec 1, 2010 at 23:06

13 votes

Accepted

Relationship between subrings and ideals

answered Nov 22, 2010 at 19:03

13 votes

What are good books/other readings for elementary set theory?

answered Nov 21, 2010 at 5:25

12 votes

Accepted

A different proof of the insolubility of the quintic?

answered Nov 20, 2010 at 23:21

12 votes

Accepted

chance on throwing a six with 6 dice

answered Nov 23, 2010 at 0:29

12 votes

Accepted

How to prove the Pythagoras theorem using vectors

answered Nov 23, 2010 at 14:28

11 votes

Accepted

Proof of the formula $1+x+x^2+x^3+ \cdots +x^n =\frac{x^{n+1}-1}{x-1}$

answered Nov 24, 2010 at 15:02

11 votes

The final state of 1000 light bulbs switched on/off by 1000 people passing by

answered Nov 21, 2010 at 15:02

10 votes

Isometry in compact metric spaces

answered Nov 29, 2010 at 4:37

10 votes

Axiom of choice - to use or not to use

answered Dec 4, 2010 at 6:47

9 votes

Accepted

Multiplication of Power Series and their convergences

answered Dec 4, 2010 at 17:31

9 votes

Intuition in algebra?

answered Dec 11, 2010 at 15:26

9 votes

Symmetric polynomials and the Newton identities

answered Dec 12, 2010 at 14:13

9 votes

Accepted

Suggest a tricky method for this problem

answered Nov 29, 2010 at 6:50

9 votes

Resources/Books for Discrete Mathematics

answered Nov 14, 2010 at 4:07

8 votes

Proof that dividing irrational number by an irrational number can result in an integer?

answered Nov 24, 2010 at 21:42

8 votes

Are associates unit multiples in a commutative ring with $1$?

answered Dec 14, 2010 at 16:04

8 votes

how to read a mathematical paper?

answered Dec 8, 2010 at 6:34

7 votes

Accepted

An elementary doubt on Inequalities

answered Dec 7, 2010 at 20:07

7 votes

Computer Programs for Pure Mathematicians

answered Dec 12, 2010 at 14:39

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106 Answers

How to show that every Boolean ring is commutative?

Does $R[x] \cong S[x]$ imply $R \cong S$?

$I+J=1 \Rightarrow I^n+J^n = 1$ for ideals (or elements in GCD domain) [Freshman's Dream Binomial Theorem]

Can $n!$ be a perfect square when $n$ is an integer greater than $1$?

Intuition behind $dx \wedge dy=-dy \wedge dx$

Can I learn Calculus on the web, for free, using simple tutorials?

A Laskerian non-Noetherian ring

Limit of the nested radical $\sqrt{7+\sqrt{7+\sqrt{7+\cdots}}}$

Factorial of a non-integer number

deadline in math jobs application

Algebraic structure cheat sheet anyone?

Relationship between subrings and ideals

What are good books/other readings for elementary set theory?

A different proof of the insolubility of the quintic?

chance on throwing a six with 6 dice

How to prove the Pythagoras theorem using vectors

Proof of the formula $1+x+x^2+x^3+ \cdots +x^n =\frac{x^{n+1}-1}{x-1}$

The final state of 1000 light bulbs switched on/off by 1000 people passing by

Isometry in compact metric spaces

Axiom of choice - to use or not to use

Multiplication of Power Series and their convergences

Intuition in algebra?

Symmetric polynomials and the Newton identities

Suggest a tricky method for this problem

Resources/Books for Discrete Mathematics

Proof that dividing irrational number by an irrational number can result in an integer?

Are associates unit multiples in a commutative ring with $1$?

how to read a mathematical paper?

An elementary doubt on Inequalities

Computer Programs for Pure Mathematicians