1,156 reputation
729
bio website math.stackexchange.com/users/…
location Antarctica
age 79
visits member for 2 years, 2 months
seen Dec 16 at 5:42

Self-learning mathematics. Many thanks to those who make time to help others on the site.


Dec
1
asked Give upper and lower bound for $\left|\cos{na} + \frac{\sin{nb}}{n}\right|$
Nov
25
asked How to find the maximum and minimum of $\dfrac{\sin x}{x^2+1}$?
Nov
11
asked How to show $a_n = \frac{n+1}{n-1}$ is strictly decreasing by induction?
Jun
26
asked Showing path connected matrices of a group $G$ is a normal subgroup
Jun
21
asked Showing the topologists sine curve is connected (slight variation)
Jun
19
asked Understanding equivalent definitions of left cosets
Jun
17
asked Open sets in $\Bbb{R}^2$ and $\Bbb{R}^3$
Jun
17
asked Clarification on quotient groups
Jun
17
asked Congruence relation possible typo?
Jun
10
asked Clarification needed on finding last two digits of $9^{9^9}$
Jun
9
asked How to determine the parity of a permutation by its cycle decomposition
Jun
9
asked Can a group of order $55$ have exactly $20$ elements of order $11$? (Clarification)
Jun
8
asked Determining whether or not a group has an element of a specific order
Jun
8
asked Showing a compact metric space has a countable dense subset
Jun
7
asked What can we say about the order of a group given the order of two elements?
Jun
2
asked Find all positive integers $x$ such that $13 \mid (x^2 + 1)$
May
29
asked Showing existence of an element with order $p$
May
26
asked Finding the values of $z$ s.t. $\sum_{n=0}^{\infty} \left( \frac{z}{1+z} \right)^n$ is convergent
May
22
asked Proving $\sum_{m=0}^M \binom{m+k}{k} = \binom{k+M+1}{k+1}$
May
19
asked Proving that $X$ is a subgroup of $G$