Mathematician Chat V.floor(π)

[biccboi]

How do I do it then?

[Joey90]

[QUOTE=JohanGS;39794897]How do I do it then?[/QUOTE]
Write z = x + yi for x and y real

Then you get:

|x + (y+1)i| = |x + (y-3)i|

<=> x^2 + (y+1)^2 = x^2 + (y-3)^2

<=> y^2 + 2y + 1 = y^2 = y^2 - 6y + 9

<=> 8y = 8

<=> y = 1

So it's true whenever y = 1...

i.e. [b]z = x + i[/b]

But x can be anything (real)!

[JohnnyMo]

Someone in my topology class just said to the professor, "I'm trying to prove the Goldbach Conjecture."

How interesting please tell me more

[Ybbat]

This man sounds like he is the future of our mathematical studies.

[Bradyns]

[QUOTE=JohnnyMo1;39796776]Someone in my topology class just said to the professor, "I'm trying to prove the Goldbach Conjecture."

How interesting please tell me more[/QUOTE]

Would laugh my ass off if he walks in next Monday with a proof. :v:

[Number-41]

[QUOTE=JohnnyMo1;39796776]Someone in my topology class just said to the professor, "I'm trying to prove the Goldbach Conjecture."

How interesting please tell me more[/QUOTE]

Reminds me of the time where I walked into piano class (first year) and I said I had the sheet music for this tune and claimed that "I just have start off at a really low BPM and gradually increase it"

[video=youtube;GQ-NAgDpRVs]http://www.youtube.com/watch?v=GQ-NAgDpRVs[/video]

Needless to say I gave up after half a measure :v:

It's never a bad thing to try stuff that is way beyond your abilities, it only makes you appreciate "the greats" even more IMO...

[JohnnyMo]

That song doesn't sound as good that fast. The recording I have is a bit slower.

[Number-41]

Yeah it's just Richter going "because I can"

[Greenandred]

I'm drawing a complete blank on separation of variables for the Laplacian in three dimensions (treating psi as a product X(x)Y(y)Z(z)). I can do it in Laplace's equation with the first term equaling a constant -l^2, the second a constant -m^2 and the third l^2+m^2, but I'm not sure what to do when there's already a non-zero constant on the RHS. I don't think it's any major change to the process, but I can't dig up any past encounters with this, and looking around the Internet hasn't yielded too much.

[IMG]http://latex.codecogs.com/gif.latex?\nabla^2%20\psi%20=%20-k^2\psi%20\\%20\\%20\frac{1}{X}\frac{dX}{dx}%20+%20\frac{1}{Y}\frac{dY}{dy}%20+%20\frac{1}{Z}\frac{dZ}{dz}%20=%20-k^2[/IMG]

[Number-41]

Alright I think I am going crazy, I'm doing a "Fundamental Mathematical Structures Course" because I want to learn about metric spaces & stuff, and an online test (which will partially contribute to 50% of the final score) asked the following:

[QUOTE]Consider A={1,2} and B={3,4}, and R={ (1,2), (1,3), (1,4), (2,3), (2,4), (3,4) }.

Check all correct answers:

R is a relation from A to B

R is a function from A to B

R is partially ordered relation from A to B

R is a surjection from A to B[/QUOTE]

Is it me or is the question itself flawed because (3,4) supposedly is an element of R, which does not make it a relation from A to B because 3 is not an element of A. So that rules out any of the other answers because a function is a relation and a surjection is a function (thus relation).

Oh and you HAVE to pick an answer...

[JohnnyMo]

Pretty sure you're right.

[Number-41]

Sent an email to the professor, I bet he will carry over his function to me instantly and plead to never practice maths again.

Or an extra mark is also welcome,

or just confirmation that the question was wrong...

[Jo The Shmo]

[url]http://www.cs.mcgill.ca/~blanchem/250/hw4/Homework4-2013.pdf[/url]

fuck this assignment, its so tedious

[Number-41]

Eww no LaTeX=gross

[JohnnyMo]

[QUOTE=Number-41;39813436]Eww no LaTeX=gross[/QUOTE]

I always wanna puke when I get an assignment sheet and it's not LaTeXed. The math professors who teach senior level math courses always use LaTeX though. They know where it's at.

[Jo The Shmo]

this would be much harder to understand if it was latexed, since you can't latex the syntax that you're inputting into your program

[editline]6th March 2013[/editline]

you have to think of it as one long string or it will be ridiculously hard to figure out

[Number-41]

There's packages for that

there are packages for everything

[swebonny]

[QUOTE=Number-41;39818132]There's packages for that

there are packages for everything[/QUOTE]

My biggest trouble was embedding images inside Latex documents. Fuck they would never stay in the place I'd like them to.

[Number-41]

Yeah they're sensitive things, those figures :v: you gotta treat 'em with respect, like those birds from Harry Potter.

Ok so apparently the right answer was nothing, even though the test yelled at you with all sorts of warnings if you didn't fill in anything. Sucks... Still got a 13/15, but dangit I could've had a 14!

[DoctorSalt]

Hey, I've been having a lot of trouble figuring out of a problem of mine: In R^3, if you had a vector that you reflected over the normals of 2 different planes, are the two transformations commutative? I believe linear transformations are commutative within their own type but not between types. Ideas?

[JohnnyMo]

Pretty sure I rocked this topology take-home midterm. Not 100% sure on the product topology and box topology closure/interior questions, but I provided good reasoning for partial credit if I fucked up and those questions are only 2.5% apiece.

[editline]6th March 2013[/editline]

Someone asked about those exact ones so my professor is going over them. Looks like I got them all right. :D

[Joey90]

[QUOTE=DoctorSalt;39821242]Hey, I've been having a lot of trouble figuring out of a problem of mine: In R^3, if you had a vector that you reflected over the normals of 2 different planes, are the two transformations commutative? I believe linear transformations are commutative within their own type but not between types. Ideas?[/QUOTE]
Try an example in R[sup]2[/sup]

See if when you reflect something in the x-axis and then in the line y=x you get the same answer as doing it in the other order...

(You can do this just by inspection)

[sp]It turns out that the composition of two reflections (in non parallel hyperplanes) is a rotation of twice the angle between them, and if you compose in the opposite order you get a rotation in the opposite direction.[/sp]
[sp]Hence they only commute if that rotation is by 0 or pi - which means the original planes were perpendicular[/sp]

[JohnnyMo]

[url]http://www.reddit.com/r/math/comments/19tgix/how_do_you_get_over_feeling_like_an_imposter/[/url]

This thread is actually quite inspiring. It's kind of amazing how common the "I'm too dumb for this" feeling is in mathematics.

[Joey90]

[QUOTE=JohnnyMo1;39831623][url]http://www.reddit.com/r/math/comments/19tgix/how_do_you_get_over_feeling_like_an_imposter/[/url]

This thread is actually quite inspiring. It's kind of amazing how common the "I'm too dumb for this" feeling is in mathematics.[/QUOTE]
One of my old Director of Studies' put it something like this - Everyone has a point in maths where they can no longer just 'get it'... For most people that point is somewhere in school, but even at university every year 2/3 or more of the people will hit the point where they can't [i]really[/i] understand it without working really hard. He said it continues all the way up into PhD's and research...

Of course the reason he was telling us was to get us to get into the habit of working hard even if you don't find it too hard yet, since it's only a matter of time until you hit your brick wall.

[Jo The Shmo]

the last time there was anyone who understood the whole of mathematics at the time was at the turn of the century
that's why it always feels like there are people out there much smarter than you, even though they might struggle in fields you understand well

[Bradyns]

My pet hate:

Stranger:
"Hey, what are you studying?"

Me:
"Mathematics.."

Possible responses:
"I hate maths!"
"I suck at maths!"
"You must be really smart." <-- This one frustrates me quite a lot, as it's merely practice.

The collective societal hate of maths, and the allowing of this mentality eviscerates me.

[Number-41]

I'm glad I did a year of conservatory before physics, as music appears so much more interesting to people. It's kinda my "disclaimer" and they ignore physics as much as possible (or they try to get me to mentor them because they reaaaaaaaaaally need to pass their introductory physics college course (yes I'm looking at you veterinarians/doctors))...

[Nikita]

The only time I can honestly say I understand a math concept is when I can visualize it as a set of geometrical or real-life properties.

E.g. integral is the area under the graph, and also a cumulative effect (of sorts) of something happening for the length of something else.

And matrices can often be visualized as planes in 3d-space and angles between vectors, and then saying "and the same thing happens in the rest of the dimensions" for big matrices.

If I can't visualize it, I feel like I don't understand it at all (and that I'm going to fail a quiz on it).

[Jo The Shmo]

[QUOTE=Bradyns;39838053]My pet hate:

Stranger:
"Hey, what are you studying?"

Me:
"Mathematics.."

Possible responses:
"I hate maths!"
"I suck at maths!"
"You must be really smart." <-- This one frustrates me quite a lot, as it's merely practice.

The collective societal hate of maths, and the allowing of this mentality eviscerates me.[/QUOTE]

you have to look at it from a new perspective
math is a [i]very[/i] abstract idea and its not at all a natural way of thinking
yes the natural world behaves according to mathematical laws, but the way our brain works is not in the slightest mathematical
some people are lucky and they can get a strong grasp on math which leads them to highly academic careers
but for a large portion of people, math is simply a weird thing that they dont need to think about very much
there is some truth to when people say "everything about math that i need i learned in elementary school!"
its not completely true, but for the large majority of the population, there never comes a moment where they need to use anything but basic arithmetic and algebra

[Glorbo]

[QUOTE=Jo The Shmo;39839444]
its not completely true, but for the large majority of the population, there never comes a moment where they need to use anything but basic arithmetic and algebra[/QUOTE]

And for some reason, everybody thinks they understand statistics