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| bio | website | math.ubc.ca/~israel |
|---|---|---|
| location | Richmond, Canada | |
| age | ||
| visits | member for | 2 years, 2 months |
| seen | 5 hours ago | |
| stats | profile views | 8,643 |
I'm an Emeritus Associate Professor of Mathematics at University of British Columbia and an Optimization Algorithms Researcher at D-Wave Systems in Burnaby BC
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Aug 19 |
answered | 2D transformation without rotation |
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Aug 19 |
answered | When can a random variable be written as a sum of two iid random variables? |
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Aug 19 |
comment |
Applications of the derivative. Strictly monotonic functions He means $-\sin x + 1$ is positive. |
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Aug 18 |
comment |
How to check if an integer has a prime number in it? Are you looking for a specific prime number, or are you asking whether the exists a prime number in it? |
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Aug 18 |
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Is there a connection between the diagonalization of a matrix $A$ and that of the product $DA$ with a diagonal matrix $D$? You might also try finding an example where $DA$ is not diagonalizable but $A$ is. |
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Aug 18 |
revised |
Looking for a function $f$ that is $n$-differentiable, but $f^{(n)}$ is not continuous deleted 61 characters in body |
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Aug 18 |
answered | Looking for a function $f$ that is $n$-differentiable, but $f^{(n)}$ is not continuous |
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Aug 18 |
answered | Weierstrass approximation to a differentiable function |
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Aug 18 |
revised |
Numerical computation of the Rayleigh-Lamb curves added 227 characters in body |
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Aug 18 |
answered | What's $F'(x)$ if $F(x) = \int_a^{g(x)} H(x,t) dt$? |
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Aug 18 |
answered | Numerical computation of the Rayleigh-Lamb curves |
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Aug 17 |
comment |
About this limit, $\lim_{t\to0^+} \sum_{n=1}^\infty \frac{\sqrt t}{1 + tn^2}$ For negative $t$ the $\sqrt{t}$ can be understood as a complex number; more serious is the $1+ t n^2$ is the denominator, which makes the $n$th term undefined at $t = -1/n^2$. These discontinuities are not removable. The limit as $t \to 0-$ does not exist because there is no interval $(-\epsilon,0)$ on which your function is defined. |
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Aug 17 |
comment |
Centroid under the Chebyshev distance What grid points? Yes, minimizing the sum of $L_\infty$ distances of points in the plane corresponds to minimizing the sum of $L_1$ distances after rotating by 45 degrees, and this can be obtained by medians in the rotated coordinates. |
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Aug 17 |
comment |
Fermat's last theorem — Google and PCMag.com Which portrait? The one at pcmag.com/article2/0,2817,2391245,00.asp now is the same as in Wikipedia en.wikipedia.org/wiki/File:Pierre_de_Fermat.jpg: maybe it has been changed. However, I found a Kepler portrait labelled as Fermat at news.m3n4.com/general/2011/pierre-de-fermat |
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Aug 17 |
answered | A tricky series problem |
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Aug 17 |
comment |
Is it possible for the number created by ordering $1$ to $n$ where $n > 1$ be a palindrome? In base 3, lots of solutions, including (1)(10)(2)(12)(22)(21)(20)(11). |
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Aug 16 |
comment |
Are there functions satisfying the following integral condition? I'm confused. Theo, were you commenting on a different version of the answer than what is there now? |
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Aug 16 |
answered | Are there any applications of Fourier series/analysis in General relativity |
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Aug 16 |
answered | Can a vertical line be a valid PDF? |
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Aug 15 |
answered | Lagrange multipliers with non-smooth constraints |
