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location Buenos Aires, Argentina
age 21
visits member for 3 years, 11 months
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Feb
5
answered Evaluating $\int \frac{1}{\sqrt{x^2 + a^2}}\, dx$ without resorting to trigonometric $u$-substitution
Feb
5
comment Evaluating $\int \frac{1}{\sqrt{x^2 + a^2}}\, dx$ without resorting to trigonometric $u$-substitution
Would you accept hyperbolic functions? :)
Jan
27
revised Find limit when $\theta$ tends to $0$ of $\tan(\theta) /\theta$
added 10 characters in body
Jan
7
answered Indefinite integral question.
Jan
6
reviewed Approve suggested edit on How to form a differential equation, given temperature and direction of heat flow
Jan
5
reviewed Reject suggested edit on Prove that $4$ is the only solution to $2+2$.
Jan
4
revised Graphs of functions with fractional powers: $x^{p/q}$
edited tags
Jan
1
comment Is this a solution to the indefinite integral of $e^{-x^2}$?
This is a nice idea, but I'm sorry to tell you that there's proof that there is no elementary formula for the integral. If you're okay with a series, just expand $ e^{-x^2} $ and integrate term by term.
Dec
30
accepted Doubts with differential geometry notation in Frankel
Dec
28
asked Doubts with differential geometry notation in Frankel
Dec
13
comment Can integration get the real value of $\pi$?
@user3015600: You could, in principle, get $\pi$ with infinite precision. If you want any digit of the decimal expansion of $\pi$, there's a zillion formulas that you can use to get it. The problem is that we can never know all of them, not because math doesn't work, but simply because there's infinitely many of them and we don't have infinite time.
Dec
13
answered Can integration get the real value of $\pi$?
Dec
10
comment Explain complex numbers
Also, I think this is a duplicate: math.stackexchange.com/questions/251665/…
Dec
10
comment Explain complex numbers
@tandberg: You can't always explain something at a level the other person can understand. If your cousin is familiar with the plane and a bit of analytic geometry, you can make the connection there. Otherwise, I'm not sure.
Dec
6
awarded  Custodian
Dec
6
reviewed Leave Open Are all good mathematicians fluent in computational aspects of mathematics
Dec
6
reviewed Edit suggested edit on Using Laplace transform to solve an IVP
Dec
6
revised Using Laplace transform to solve an IVP
improved formatting
Nov
29
answered The arithmetic mean of $X$ when arithmetic mean of $X^2 = 29$.
Nov
25
comment $2\times2$ matrices are not big enough
@MarcvanLeeuwen: The reason I made my comment is that yours seemed to imply that this isn't a very good example because it's not evident how to define a rotation matrix for $n > 2$ dimensions. I just wanted to make clear that $3$-dimensional rotation matrices are easy to define and don't commute, that's all.