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bio website linkedin.com/in/gt6989b
location New York, NY
age 36
visits member for 3 years, 3 months
seen Dec 17 at 4:26

Jan
2
comment Evaluating sign of inequality under constraint
@tomka What is more interesting is to find the entire range of values of $a$ where it is true and false...
Jan
2
comment Evaluating sign of inequality under constraint
for some real $a$? Try $a=0$ :-). Do you mean for any real $a$?
Jan
2
comment Deciding whether this integral is convergent or divergent: $\int_1^\infty \frac{e^{\sqrt {x}}}{\sqrt{x}}\,\mathrm dx$
@Pumpkin if you sub correctly your integral becomes $\int e^{-y}$...
Jan
2
comment Deciding whether this integral is convergent or divergent: $\int_1^\infty \frac{e^{\sqrt {x}}}{\sqrt{x}}\,\mathrm dx$
The last step should likely read $<x^{-1.5}$ and the integral as well, which would actually make it convergent :-) since $\int_0^\infty x^{1.5} dx = + \infty$...
Jan
2
comment detecting dynamic parts in graph
Hi, welcome to Math.SE! Thanks for your question, it looks interesting but I could not really comprehend what you are asking. Could you consider giving an example?
Dec
30
comment Delete a vertex,how to show that graph remains connected?
May help to post a definition of a coherent graph, I don't think it's commonly known. I found one here on p.10: idsia.ch/~zaffalon/papers/2009aij-cgs.pdf (Def.9).
Dec
30
comment What is the CPLX button on a calculator?
@DantheMan here is a brief summary in Russian if it helps (1okey.ru/privat/instruction/instruction/…). They do agree that CPLX means a register of complex numbers...
Dec
26
comment How to find whether Linear system has unique solution or not?
@Andy No. The 4th row has the first 3 entries of 0 and the last one is $f$. The last equation reads $0 x_1 + 0 x_2 + 0 x_3 = f$, so if $f \neq 0$, there are no solutions.
Dec
26
comment Inequality Case by Case way
@franck $x$ changes sign at 0.
Dec
26
comment A logical problem I can't solve. Please help. (About money)
Not sure what you are asking. You ate 45 worth of food and still have 1 left (total 46), for which you compensated by returning 23 to 2 people at the same time...
Dec
26
comment A logical problem I can't solve. Please help. (About money)
@Wicht retagged
Dec
26
comment Elementary number theory problem
@ErickWong Thanks, totally missed that $n \in X$.
Dec
26
comment Elementary number theory problem
@mathlove How does 22 consist of 1 or 3?
Dec
26
comment Inverse image$f^{-1}(\{-9\})$
@depecheSoul he likely means $f(x)$ not $f(X)$...
Dec
23
comment Conditional Probabilities and non-zero condtions
@Moses please see the edit...
Dec
23
comment Dose any one know a good book about finding graph by equations?
Why not just plot it, e.g. with Wolfram Alpha?
Dec
23
comment Find $f(x)$ where $ f(x)+f\left(\frac{1-x}x\right)=x$
If we assume $f$ is differentiable, perhaps the equation for the derivative is easier: $$ f'(x) - x^{-2} f'\left(\frac{1-x}{x}\right) = 1 $$
Dec
19
comment trouble understanding integration
@YuriSwarovski good to be of help. Andre Nicolas did all the work with his note, this was just working out the arithmetic.
Dec
18
comment Query on Mean Value Theorem Criteria
What is the question? Why don't you need differentiability at the endpoints?
Dec
18
comment Double Integration Problem for Buffon's Needle experiment
@bukka glad to be of help