User Ishan Banerjee

35 votes

6 answers

25k views

$AB-BA=I$ having no solutions

matrices matrix-equations

asked Jan 23, 2013 at 9:21

16 votes

2 answers

873 views

Evaluating $\int_0^{\infty}\frac{e^{-x}}{1+x^2}dx$

asked Apr 3, 2013 at 12:24

15 votes

4 answers

668 views

Finding $\int^1_0 \frac{\log(1+x)}{x}dx$ without series expansion

real-analysis calculus integration improper-integrals

asked Jan 28, 2013 at 10:23

13 votes

1 answer

2k views

Rational points on a circle with centre $(\pi, e)$

geometry elementary-number-theory

asked Feb 27, 2013 at 10:22

10 votes

3 answers

753 views

Value of $\sum_{k=1}^{\infty}\frac{1}{k^2+a^2}$

real-analysis sequences-and-series

asked Feb 26, 2013 at 16:16

7 votes

2 answers

933 views

Uniqueness of Tetration

functional-equations tetration

asked Jan 23, 2013 at 7:55

7 votes

4 answers

299 views

Intermediate value-like theorem for $\mathbb{C}$?

analysis continuity

asked Apr 19, 2013 at 14:32

7 votes

1 answer

145 views

Limit of $a_{k+1}=\dfrac{a_k+b_k}{2}$, $b_{k+1}=\sqrt{a_kb_k}$?

real-analysis sequences-and-series limits

asked Mar 31, 2013 at 13:31

6 votes

1 answer

1k views

Convergence of nested radicals

real-analysis convergence-divergence nested-radicals

asked Mar 6, 2013 at 16:17

4 votes

1 answer

61 views

How does this method to find the centre work?

geometry analytic-geometry conic-sections

asked Mar 25, 2013 at 13:42

4 votes

1 answer

2k views

A Limit of a sum related to the exponential series.

calculus sequences-and-series limits

asked Feb 22, 2013 at 10:48

4 votes

3 answers

828 views

Why can't this be a coset?

abstract-algebra group-theory

asked May 13, 2013 at 10:00

3 votes

1 answer

86 views

Approximating an integral with elementary functions

calculus asymptotics improper-integrals

asked Jun 14, 2013 at 12:09

3 votes

1 answer

380 views

Tangent space to lie group at identity.

differential-geometry lie-groups

asked Oct 22, 2014 at 19:34

2 votes

2 answers

327 views

Problem with understanding proof of Van Kampen's theorem

algebraic-topology

asked Oct 20, 2014 at 13:55

2 votes

2 answers

191 views

Set of natural number solutions to $x^2+y^2=z^2$

elementary-number-theory diophantine-equations

asked Feb 14, 2013 at 16:05

2 votes

1 answer

100 views

Limit of a 31st order linear recurrence

sequences-and-series limits

asked Mar 24, 2013 at 13:29

1 vote

2 answers

355 views

Lemma about Brouwer degree in Milnor's book

differential-topology

asked Jun 4, 2015 at 14:22

1 vote

1 answer

56 views

Countably many APs partitioning the natural numbers

elementary-number-theory

asked Oct 12, 2014 at 6:40

Stack Exchange Network

current community

your communities

more stack exchange communities

19 Questions

$AB-BA=I$ having no solutions

Evaluating $\int_0^{\infty}\frac{e^{-x}}{1+x^2}dx$

Finding $\int^1_0 \frac{\log(1+x)}{x}dx$ without series expansion

Rational points on a circle with centre $(\pi, e)$

Value of $\sum_{k=1}^{\infty}\frac{1}{k^2+a^2}$

Uniqueness of Tetration

Intermediate value-like theorem for $\mathbb{C}$?

Limit of $a_{k+1}=\dfrac{a_k+b_k}{2}$, $b_{k+1}=\sqrt{a_kb_k}$?

Convergence of nested radicals

How does this method to find the centre work?

A Limit of a sum related to the exponential series.

Why can't this be a coset?

Approximating an integral with elementary functions

Tangent space to lie group at identity.

Problem with understanding proof of Van Kampen's theorem

Set of natural number solutions to $x^2+y^2=z^2$

Limit of a 31st order linear recurrence

Lemma about Brouwer degree in Milnor's book

Countably many APs partitioning the natural numbers