123,126 reputation
478206
bio website math.ubc.ca/~israel
location Richmond, Canada
age
visits member for 3 years, 4 months
seen 12 hours ago

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


Jul
14
answered Putnam Exam question
Jul
13
answered unbiased estimator in a random sample
Jul
13
comment What are the properties of the set of the Real Numbers without the Integers?
Any finite ant can step over the missing number without even noticing it.
Jul
13
comment How to find all possible values of Ɵ for the equation cos4Ɵ=0
Do you know where $\cos(t) = 0$?
Jul
13
comment What's this number called and what are its properties?
OK, so let's give it a name: "user132181's number".
Jul
13
answered Prove that $1-2^{-x}\geq \frac{\sqrt 2}{2}\sin\left(\frac{\pi}{4} x\right)$
Jul
13
answered Differentiation - Equilibria
Jul
12
answered Count 1-bit in binary integers
Jul
11
answered Show that $\sum_{k=1}^{n}a_ke^{2 \pi ikx}$ has a root in $\left[ 0,1 \right]$
Jul
11
answered A homework question, finding the maximum possible value of the sum of two remainders
Jul
11
answered Non-examples for the Kato-Rellich Theorem
Jul
11
comment Why is $\sum_{i=0}^{n}1=(n+1)$?
You aren't "adding nothing", you are adding $1$ for each value of $i$ from $0$ to $n$.
Jul
11
comment Matrices and algebra
The Maple command is: product((x^3+1)/(x^3-1), x=2..infinity);
Jul
9
answered How many patterns?
Jul
9
comment Matrices and algebra
According to Maple, $$\prod_{x=2}^\infty \dfrac{x^3+1}{x^3-1} = \dfrac{3}{2}$$
Jul
8
answered Matrices and algebra
Jul
8
comment How to determine if it is l'Hopital's or not?
@Brad: didn't you contradict this statement in your answer? $\lim_{x \to \infty} \dfrac{x+\sin(x)}{x}$ is a case where "the denominator is infinite" (i.e. has an infinite limit) and l'Hopital's rule can't be used.
Jul
7
answered Laplace transform non exponential order.
Jul
7
answered How does this discontinuity occur in evaluating a nested square root?
Jul
6
comment Joint probability of two conditional probabilities
What does $A|B \cap B|A$ mean? Note that $A|B$ and $B|A$ are not events.