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location Minneapolis, MN
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visits member for 3 years, 3 months
seen 10 hours ago

I have a Ph.D. with a minor in mathematics and a major in statistics.


9h
revised Why $\int {dx \over x \sqrt{x+3}} \neq \int {2u\cdot du \over (u^2-3)u} \rvert_{u=\sqrt{x+3}} $?
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10h
reviewed Edit suggested edit on Following flash, a camera's battery begins to recharge the flash’s capacitor, which stores electric charge given by $Q(t) = Q_0(1 − e^{−t/a})$
10h
revised Following flash, a camera's battery begins to recharge the flash’s capacitor, which stores electric charge given by $Q(t) = Q_0(1 − e^{−t/a})$
improved formatting of the title
13h
revised Let $Q$ be a symmetric $n$ by $n$ matrix, there exists an orthogonal matrix $F$ such that $F^TQF=\operatorname{diag}(\lambda_1,\ldots,\lambda_n)$
added 21 characters in body; edited title
13h
revised Law of total probability in continous case
proper use of \mid
13h
comment Question about notations involving $\sup$ and $\inf$
It may be that someone used the notation $\{\sup_n f_n>a\}$ to mean the set $\{x : \sup_n f_n(x)>a\}$, and $\{f_n>a\}$ to mean $\{x : f_n(x)>a\}$. ${}\qquad{}$
13h
comment Correctness of proof that an ordered field S that has the supremum property also has the infimum property
@matsmv: What you are trying to prove is that every non-empty set that is bounded below has a greatest lower bound, given that every non-empty set that is bounded above has a smallest upper bound. So you need to assume a set is non-empty and bounded below, and then prove that it has a greatest lower bound. The way you do that involves looking at the smallest upper bound of the set of all lower bounds.
14h
answered Question about notations involving $\sup$ and $\inf$
18h
revised Analog of the Chebyshev's inequality
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18h
comment quotas for the expected value
The question posed in the first sentence is one that I have answered here several times.
18h
revised Conditional probability plane problem
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18h
revised Proof by induction
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18h
revised Fourier transform of Bessel Function Second Kind
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18h
revised Why adding a club of $\aleph_1$ collapses $\aleph_1$ to $\aleph_0$?
added 3 characters in body
18h
answered Correctness of proof that an ordered field S that has the supremum property also has the infimum property
22h
revised “Taking expectation” to yield conditional probability
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22h
revised Expressing $U_{xy}$ via Multivariable chain rule
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22h
revised Proving differentiable function is continuous.
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22h
revised Help Evaluating $\lim_{x\to\infty}\left(\cos\frac{3}{x}\right)^{x^2}$
edited body
22h
reviewed Edit suggested edit on About a sequence of $p$-harmonic functions