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Visiting Assistant Professor of Mathematics at Swarthmore College


Dec
17
comment Calculate the variance of $Y=2X+7$
$E[X^2] \neq E[X]^2$
Dec
16
comment Prove ${x:d(x,p) < d(x,q)}$ is open in metric space $X$
I edited. You should also look at your definition of $N_r(x)$. I think it should be $N_r(x) = \{y:d(x,y) < r\}$.
Dec
16
revised Prove ${x:d(x,p) < d(x,q)}$ is open in metric space $X$
added 746 characters in body
Dec
16
answered Prove ${x:d(x,p) < d(x,q)}$ is open in metric space $X$
Dec
15
comment Projection of vectors
How are you calculating that $0$?
Dec
15
reviewed Approve How to find out whether a group is Abelian
Dec
15
reviewed Approve Mathematical induction to proof
Dec
15
comment Is the series $\sum_{n=1}^\infty\frac{n-1}{n+\ln n}$ convergent?
Yes, one condition that is necessary for a series $\sum a_n$ to converge is that $\lim_{n \to \infty} a_n = 0$.
Dec
15
answered How to integrate using known distributions
Dec
15
comment How to integrate using known distributions
You could also substitute $u = x^2$ and then do integration by parts...
Dec
15
comment Is the series $\sum_{n=1}^\infty\frac{n-1}{n+\ln n}$ convergent?
That is a very good question. What happens when I try to take an infinite sum of numbers that approach $1$?
Dec
15
comment Some questions about the Eigenvalues of this $4\times 4$ matrix
Win some, lose some, I guess. :)
Dec
15
answered Some questions about the Eigenvalues of this $4\times 4$ matrix
Dec
15
answered Is the series $\sum_{n=1}^\infty\frac{n-1}{n+\ln n}$ convergent?
Dec
15
comment $a_1^3+a_2^3+…+a_n^3=0 \Rightarrow a_1+a_2+…+a_n=0$ it is true or not?
What have you tried?
Dec
15
reviewed Approve Differentiability of a function
Dec
14
revised How many finite sequnces $x_1,x_2,x_3,\ldots,x_m$ are there such that $x_i =1$ or $2$ and $\sum_{i=1}^{m}x_i=10$
edited body
Dec
14
answered How many finite sequnces $x_1,x_2,x_3,\ldots,x_m$ are there such that $x_i =1$ or $2$ and $\sum_{i=1}^{m}x_i=10$
Dec
14
reviewed Edit Find two functions $f$ and $g$ such that they are both discontinuous at $c$, however, $f+g$ and $f\cdot g$ are both continuous at $c$
Dec
14
revised Find two functions $f$ and $g$ such that they are both discontinuous at $c$, however, $f+g$ and $f\cdot g$ are both continuous at $c$
improved formatting