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bio website people.math.osu.edu/edgar.2
location Denver, CO
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visits member for 4 years
seen 8 hours ago

Jul
21
comment Tough equation in my entry exam
I think we need the exact wording from the entrance exam. Are we sure it did not say: "Find all integer solutions" ... or "How many real solutions are there" ??
Jul
21
comment The Name for $\mathbb{R}$, $\mathbb{C}$, $\mathbb{H}$ and $\mathbb{O}$ Exclusively Algebras?
That wikipedia page suggests you should say "normed division algebras with unity". Unless, of course, your definition of "algebra" includes "with unity" already.
Jul
20
comment A trouble with the discrete product topology
It is true that the description you quote is not for "the open sets" but for a base for the open sets. Your set $B$ is a finite union of sets of type $A$.
Jul
17
answered How is $\,\int(1/x)\,dx = \ln|x|\,$ true?
Jul
16
comment Do we need the $f,g \geq 0$ condition for $\int f \ d\mu = \int g \ d\mu$?
If the two integrals are both undefined, should we say they are equal anyway?
Jul
14
awarded  Nice Answer
Jul
11
answered How to create circles and or sections of a circle when the centre is inaccessible
Jul
11
answered Series Ratio Test Convergence
Jul
10
awarded  Nice Answer
Jul
9
comment Converting x number of petaFLOPS into a base 2 number
So, what definitions are you using.... one petaFLOPS is $10^{15}$ FLOPS? or $2^{50}$ FLOPS? (similar to the question of whether a kilobyte is $1000$ byes or $1024$ bytes.)
Jul
6
answered Are indefinite integrals unique up to the constant of integration?
Jul
6
comment Is $\cup_{k=1}^\infty (r_k-\frac{1}{k}, r_k+\frac{1}{k}) = \mathbb{R}$?
@Rene: since the first term in the sum has measure 2.
Jul
2
comment What is the solution of cos(x)=x?
I believe there is no known way to write this solution in terms of the Lambert W function.
Jul
1
comment Solve logarithmic equation: $2\log_7 (x+2) - \log_7 (3x+10) = 0$
No, that is not the right answer. The answer would have the form x = (something not involving x).
Jun
30
comment correct Set theory notations.
Note, in his quotation, they are not talking about "the" universal set, but rather "a" universal set: the set of all objects to be discussed. Represented by the outside rectangle in the Venn diagram. So: If we are doing number theory, we may consider a universal set $\{1,2,3,\dots\}$.
Jun
29
comment Positive Operators: Definition?
I seem to remember that the numerical range and the spectrum have the same convex hull. Is that right? If so, then one is positive iff the other is.
Jun
27
comment What are the most important functions every mathematician should know?
I see the question has not been declared CW. Presumably this means we expect one definitive answer.
Jun
27
comment What are the most important functions every mathematician should know?
What is $sh$? I assume it is not $\sinh$, since you also write $\cosh$ and not $ch$.
Jun
27
comment How were 'old-school' mathematics graphics created?
What is this plotting program you mention? "Old-school" illustrations precede computers!
Jun
27
comment What are the most important functions every mathematician should know?
So ... the list of functions a number-theorist should know differs from the list of functions an applied mathematician should know.