1d
answered How to create circles and or sections of a circle when the centre is inaccessible
1d
answered Series Ratio Test Convergence
2d
awarded Nice Answer
Jul
10
comment Is there an app that lets me use an iPhone as a mouse?
absolute positioning is very difficult using the sensors available in an iPhone interesting idea ... use GPS to get the position of the iPhone accurately enough to serve as a mouse... :)
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
9
comment Did Vernor Vinge originate the euphemism "you-gotta-believe-me"?
Interesting. I took "turn of the century" to mean around 1900. (Since the book was written before 2000.) But the book is set after 2000, so it may mean around 2000. Maybe Rainbows End (note: no apostrophe) is the book that popularized the phrase...
Jul
6
comment Base change for $\sqrt{2}.$
$\theta_{11}$ is certainly irrational. There is a well-known (but still far from proved) conjecture that all algebraic irrationals are normal in all bases. So (of course) your number is transcendental. But your question (whether there is an easy proof of it) is not answered by this.
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
5
comment Integral of Bessel function of 1st kind with complex exponential
Can you do this special case? $$\int _{0}^{t}\!{{\rm J}_1(s)}{{\rm e}^{-2\,i ( t-s ) }}{ds} $$
Jul
4
revised Angles and proportions occurring in L-system fractals
added 3126 characters in body
Jul
4
revised Angles and proportions occurring in L-system fractals
added 3126 characters in body
Jul
4
revised Angles and proportions occurring in L-system fractals
added 3126 characters in body
Jul
3
comment closed form expression for an infinite series
Are there nontrivial special cases you can do? Say, $u=1$?
Jul
3
answered Angles and proportions occurring in L-system fractals
Jul
2
comment asking questions outside of field of expertise
There is an opposite problem I have seen. A good question is asked, but non-experts vote to close it, mistakenly thinking it is just an exercise.
Jul
2
comment schanuel's conjecture and real root of $x+e^x=0$
Side remark... This number is $-W(1)$, where $W$ is the Lambert W-function.
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 $\{1,2,3,\dots\}$.
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