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As somebody used to say:

Does research. Smokes. Battles administration. Smokes. Wishes he could stop battling administration so that he could have more time to do research. Smokes some more.

The same. Except I do not smoke.


How to ask a good question?

This paragraph is for my personal use but freely available:

Welcome to Math.SE! Please, consider updating your question to include what you have tried and where you are getting stuck. That way, people on this site will know exactly what help you need.


2d
revised Value of the integral $\int_0^{2\pi}\int_0^{2\pi}\delta(k_2\cdot e^{i\theta}+k_3\cdot e^{j\phi} +z )d\theta d\phi$
added 12 characters in body; edited tags; edited title
2d
revised Value of the integral $\int_0^{2\pi}\int_0^{2\pi}\delta(k_2\cdot e^{i\theta}+k_3\cdot e^{j\phi} +z )d\theta d\phi$
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2d
comment Value of the integral $\int_0^{2\pi}\int_0^{2\pi}\delta(k_2\cdot e^{i\theta}+k_3\cdot e^{j\phi} +z )d\theta d\phi$
It does very much depend on $z$ since it is zero when $z\ne0$ and may be nonzero when $z=0$. Likewise for $k_3$ (which I called $k_1$, will change that).
2d
answered Value of the integral $\int_0^{2\pi}\int_0^{2\pi}\delta(k_2\cdot e^{i\theta}+k_3\cdot e^{j\phi} +z )d\theta d\phi$
2d
comment Value of the integral $\int_0^{2\pi}\int_0^{2\pi}\delta(k_2\cdot e^{i\theta}+k_3\cdot e^{j\phi} +z )d\theta d\phi$
math.stackexchange.com/q/937829
2d
comment Probability of impossible event.
How is the portion of ‘impossible’ out of the total possibility informing us about the portion of ‘possible’ out of the total possibility (whatever these strings of words actually mean)?
2d
comment Probability of impossible event.
To call an event impossible because "it is not known ahead of time if an event is possible or impossible" strikes me as a very peculiar use of the English language.
2d
revised How to solve $y'=\frac {e^{x-y}}{y-1}$?
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2d
revised How to solve $y'=\frac {e^{x-y}}{y-1}$?
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2d
comment How to solve $y'=\frac {e^{x-y}}{y-1}$?
((And yet another example of "accepting" an answer much too hastily.))
2d
revised How to solve $y'=\frac {e^{x-y}}{y-1}$?
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2d
comment How to solve $y'=\frac {e^{x-y}}{y-1}$?
@ClaudeLeibovici You might not be the most stupid person in the room... :-) A (not very difficult) supplementary argument is needed to determine whether $y(x_0)$ is equal to $-1$ or to "your" solution.
2d
revised How to solve $y'=\frac {e^{x-y}}{y-1}$?
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2d
revised How to solve $y'=\frac {e^{x-y}}{y-1}$?
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2d
answered How to solve $y'=\frac {e^{x-y}}{y-1}$?
2d
comment Solving $ \frac{dy}{dx} = y^2 - 9$
This answer is not correct. If one follows closely what is written, one sees that C must be positive hence the final formula misses quite a few solutions. The implication between an identity with absolute values and an identity without absolute values (beginning of line 3), in particular, is, frankly speaking, a mystery (and not correct).
2d
comment One-Dimensional Maps
Your objective is to use graphical analysis, but where is your graphics?
2d
comment How to determine the orbits of points under the tripling map $f(x)=3x\bmod 1$?
Wait, you cannot determine the orbit of $\frac18$?
2d
comment Periodic Points Homework Help
Really you cannot "Make a table for 1≤k≤4 showing the following: (i) k, (ii) the number of fixed points of fk"? That would be a start.
2d
revised Fourier series of function $f(x)=0$ if $-\pi<x<0$ and $f(x)=\sin(x)$ if $0<x<\pi$
edited title