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3h
revised Why is this the closed-form solution for this series?
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3h
answered Why is this the closed-form solution for this series?
3h
revised Why is this the closed-form solution for this series?
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4h
revised When is the conditional expectation function equal to a continuous function a.e.?
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4h
answered Find all $z$ such that $e^z=6i$
4h
comment Multivariate normal value standardization
For $\Sigma^{-1/2}$, I'm getting $\left[ \begin{array}{rr} 1.0415497 & -0.1035578 \\ -0.1035578 & 1.0306489 \end{array} \right]$. $\qquad$
4h
comment Multivariate normal value standardization
Working in R, if I let $B$ be the matrix $\left[\begin{array}{rr} 0.7207 & -0.0587; \\ -0.0587 & 1.0235 \end{array} \right]$, then the command solve(B)%*%solve(B), which gives the value of $(B^{-1})^2$, yields $\left[\begin{array}{rr} 1.9497729 & 0.1899401 \\ 0.1899401 & 0.9699799 \end{array} \right]$ rather than $\left[\begin{array}{rr} 0.95 & 0.19 \\ 0.19 & 0.97 \end{array} \right]$. So something is wrong with your way of trying to find $\Sigma^{-1/2}$. $\qquad$
5h
answered Multivariate normal value standardization
5h
revised Multivariate normal value standardization
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7h
revised Multivariate normal value standardization
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10h
comment Clever way of calculating the integral $ \int \frac{dt}{t^2\sqrt{t-2} } $
Three answer appeared here without anyone suggesting a rationalizing substitution. I posted that below.
10h
answered Clever way of calculating the integral $ \int \frac{dt}{t^2\sqrt{t-2} } $
10h
revised Clever way of calculating the integral $ \int \frac{dt}{t^2\sqrt{t-2} } $
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reviewed Edit conditional probability (question)
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revised conditional probability (question)
MathJax usage
10h
answered Convergent sequence of irrational numbers that has a rational limit.
10h
revised The sum of the following infinite series $\frac{4}{20}+\frac{4\cdot 7}{20\cdot 30}+\frac{4\cdot 7\cdot 10}{20\cdot 30 \cdot 40}+\cdots$
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11h
revised Show that $f(x):=\frac{2x^3+x^2+x\sin(x)}{(\exp(x)-1)^2}$ is continuously extendable to $x_0=0$.
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11h
revised How would you calculate $(200\int_0^\infty e^{-0.8t}-e^{-1.8t}\,dt)/(250\int_0^\infty e^{-0.8t} \,dt)$?
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11h
revised Proving matrix is invertible using the Banach Lemma
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