User gebruiker

18 votes

Limit $\frac{x^2y}{x^4+y^2}$ is found using polar coordinates but it is not supposed to exist.

answered May 2, 2016 at 20:09

16 votes

Among any three consecutive positive integers one is a multiple of 3

answered Jul 8, 2014 at 9:21

14 votes

Accepted

Multiplicative inverse of $0$

answered Jun 13, 2014 at 17:50

11 votes

Would this solution of the limit of the sequence be correct?

answered Feb 2, 2016 at 13:58

9 votes

Is polar coordinates enough to prove that a limit exists

answered May 3, 2016 at 7:54

8 votes

Is it necessary that if a limit exists at a point it should be also defined at that point?

answered Nov 17, 2015 at 16:06

7 votes

Accepted

Finish proving that $\lim_{n\to \infty}\frac 1{n!}=0$

answered Jan 18, 2016 at 16:02

6 votes

Why does $\vec{V_1}\times\vec{V_2}\cdot \overrightarrow{M_1M_2}\neq0$ imply that the two lines with $V_1$ and $V_2$ as direction vectors are skew?

answered Jul 8, 2016 at 11:36

5 votes

An operation on a whole is equal to an operation on each part?

answered Apr 19, 2016 at 18:11

5 votes

Accepted

Solving modulus inequality $|x - 1| + |x - 6|\le11$ geometrically

answered Mar 12, 2016 at 9:02

5 votes

Accepted

Sum of all the $x$- and $y$-intercepts of the graph of $f(x)$ is equal to the sum of all the $x$- and $y$-intercepts of the graph of $f^{-1}(x)$

answered Dec 11, 2015 at 14:25

4 votes

If limit of $f(x)$ exists and the limit of $f(x)g(x)$ exists, then does the limit of $g(x)$ exist?

answered May 26, 2014 at 14:47

4 votes

How do we get the relation: $\max\limits_{(x,y) \in \overline{D}} u(x,y) = \max\limits_{(x,y) \in \partial{D}} u(x,y)$?

answered May 12, 2014 at 14:14

3 votes

Accepted

Showing a limit does not exist using Cauchy's $\epsilon, \delta $ limit definition

answered May 7, 2014 at 15:34

3 votes

Testing for absolute convergence? $\frac{(-1)^n}{5n+1}$

answered Apr 29, 2014 at 18:39

3 votes

$(n+1)!>n^2, \forall n\ge 4$

answered Apr 25, 2014 at 14:26

3 votes

Finding a point on a circle that has a distance L (arc length) from another point

answered May 5, 2014 at 15:23

3 votes

Accepted

Proving continuity using $\epsilon$ and $\delta$

answered Dec 20, 2015 at 21:54

3 votes

Accepted

Prove equivalence between $X$ Hausdorff and $X$ finite with discrete topology

answered May 19, 2015 at 18:09

3 votes

Prove that if one function is greater or equal than another, then so it is its limit.

answered Nov 7, 2015 at 18:20

3 votes

How many $5$-digit zip codes are there with exactly $n$ odd digits?

answered Apr 13, 2018 at 14:08

3 votes

Accepted

Prove that ordinal multiplication is left distributive

answered Jun 1, 2016 at 14:39

3 votes

Line tangent to circle

answered Dec 21, 2015 at 18:53

3 votes

Obtain magnitude of square-rooted complex number

answered Jan 29, 2016 at 9:46

3 votes

Accepted

Contradictory equations

answered Mar 22, 2016 at 10:21

3 votes

Accepted

Derive the equation of first variation for a flow of a vector field.

answered Mar 25, 2016 at 11:34

3 votes

Accepted

Product of limits when one is zero and the other does not exist

answered Apr 28, 2016 at 19:41

3 votes

Accepted

Is it The Axiom of Power Set that guarantees the existence of (all) subsets?

answered Jun 19, 2016 at 7:54

3 votes

Why is the change-to-polar-coordinate method valid in computing limits?

answered Dec 7, 2016 at 10:07

3 votes

The meaning of $N_{K/K(a)}$

answered Jul 6, 2017 at 9:00

Stack Exchange Network

172 Answers

Limit $\frac{x^2y}{x^4+y^2}$ is found using polar coordinates but it is not supposed to exist.

Among any three consecutive positive integers one is a multiple of 3

Multiplicative inverse of $0$

Would this solution of the limit of the sequence be correct?

Is polar coordinates enough to prove that a limit exists

Is it necessary that if a limit exists at a point it should be also defined at that point?

Finish proving that $\lim_{n\to \infty}\frac 1{n!}=0$

Why does $\vec{V_1}\times\vec{V_2}\cdot \overrightarrow{M_1M_2}\neq0$ imply that the two lines with $V_1$ and $V_2$ as direction vectors are skew?

An operation on a whole is equal to an operation on each part?

Solving modulus inequality $|x - 1| + |x - 6|\le11$ geometrically

Sum of all the $x$- and $y$-intercepts of the graph of $f(x)$ is equal to the sum of all the $x$- and $y$-intercepts of the graph of $f^{-1}(x)$

If limit of $f(x)$ exists and the limit of $f(x)g(x)$ exists, then does the limit of $g(x)$ exist?

How do we get the relation: $\max\limits_{(x,y) \in \overline{D}} u(x,y) = \max\limits_{(x,y) \in \partial{D}} u(x,y)$?

Showing a limit does not exist using Cauchy's $\epsilon, \delta $ limit definition

Testing for absolute convergence? $\frac{(-1)^n}{5n+1}$

$(n+1)!>n^2, \forall n\ge 4$

Finding a point on a circle that has a distance L (arc length) from another point

Proving continuity using $\epsilon$ and $\delta$

Prove equivalence between $X$ Hausdorff and $X$ finite with discrete topology

Prove that if one function is greater or equal than another, then so it is its limit.

How many $5$-digit zip codes are there with exactly $n$ odd digits?

Prove that ordinal multiplication is left distributive

Line tangent to circle

Obtain magnitude of square-rooted complex number

Contradictory equations

Derive the equation of first variation for a flow of a vector field.

Product of limits when one is zero and the other does not exist

Is it The Axiom of Power Set that guarantees the existence of (all) subsets?

Why is the change-to-polar-coordinate method valid in computing limits?

The meaning of $N_{K/K(a)}$