3,933 reputation
1635
bio website
location Besançon, France
age 34
visits member for 1 year, 9 months
seen 6 hours ago

I am a statistician at INSEE, the french national institute of statistics.

Mathematics is a hobby for me, and MSE helps me not to forget too much what I learned in university (MS in applied mathematics at Lyon 1). I like especially real and complex analysis, trigonometry, numerical analysis, finite groups theory, number theory and combinatorics. I am not allergic to other fields.


Jun
24
comment Horizontal axis for reference angles
Yet another convention: you could perfectly have x>0 and y>0 in any quadrant, not necessarily the usual one. Screen images are an example where this convention is not followed, since usually the low $y$ are at the top of the screen.
Jun
23
comment Derivative in calculus $f(t)= 7\sinh(\ln t)$
If you want the derivative of this, it's of course $(2t(2t)-2(t^2-1))/(4t^2)$ (derivative of a quotient $u/v$ is $(u'v-uv')/v^2$).
Jun
23
comment equilateral triangle area geometry
You may also find this interesting: en.wikipedia.org/wiki/Koch_snowflake
Jun
23
answered Derivative in calculus $f(t)= 7\sinh(\ln t)$
Jun
23
revised equilateral triangle area geometry
added 44 characters in body
Jun
23
revised equilateral triangle area geometry
added 457 characters in body
Jun
23
comment how to solve this question of polynomials
What's the meaning of your equation (3), and the following conclusion (4)? (especially the notation $p(1,1/3)$ is rather obscure) Actually, from $p(-1)=0$ you get $(-1)h+k=0$, and from $p(1/3)=4$, $(1/3)h+k=4$.
Jun
22
reviewed Approve suggested edit on $\int_0^\pi\sin(2t)e^{-in2t}dt$ complex number integral for integer values of n
Jun
15
comment Trigonometry without sine and cosine
Since the angles involved are not "easy" (like 45° or 60°), you will inevitably need trig functions to compute exactly the height. Hence, without trig functions, either you must do a careful drawing, or you look up in Wikipedia or elsewhere the actual height of Eiffel tower...
Jun
14
comment Measuring diaognals without Sine Law
Is there a reason not to use law of cosines? The solution is very easy with it.
Jun
8
revised Heat equation with a disc
added 3 characters in body; edited title
May
29
reviewed Leave Open The product of cardinals
May
29
reviewed Leave Open If n > 1 and $B \subset \mathbb R^n$ countable. Then $\mathbb R^n - B$ is connected ( James Dugundji)
May
29
reviewed Leave Open an amazing complex integral along unit circle
May
29
revised Euler product for Riemann zeta and analytic continuation
added 12 characters in body; edited tags
May
28
comment Pearson's Chi Squared / Cochran–Mantel–Haenszel test analog to N-way ANOVA
You may try also on stats.stackexchange.com
May
28
comment Dilogarithm in closed form
At least you can tell the result is a real number (plug the dilog series expansion in your expression). Also, there may be a clever Fourier series to use.
May
28
answered Finding the absolute minimum and maximum of a function
May
28
reviewed Approve suggested edit on Finding the absolute minimum and maximum of a function
May
27
comment Fascinating Lampshade Geometry
Nevertheless, the parametric approach is very instructive, and one can rather easily rediscover all basic results of perspective, with vanishing line, etc. You simply start with a point (the eye, equivalent of the light source here), a plane (the wall), and compute projection of lines, circles...