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10101011010101 by Betsy Fuckingway - Wed, 28 Sep 2016 20:51:12 EST ID:dJCwm4mq No.15225 Ignore Report Reply Quick Reply
File: 1475110272932.jpg -(450342B / 439.79KB, 1920x1080) Thumbnail displayed, click image for full size. 450342
When u come onto the math board
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Beatrice Subberbanks - Fri, 30 Sep 2016 16:50:22 EST ID:9fX9//hV No.15231 Ignore Report Quick Reply
What in the blue fuck are you talking about?
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Charlotte Brezzlecheg - Fri, 30 Sep 2016 17:11:16 EST ID:ZD4TCLS2 No.15232 Ignore Report Quick Reply
>>15231
I think that by posting a picture of the green vertical "code" from the movie The Matrix along with a binary string for a subject the OP is trying to indicate that they felt awed by the discussions taking place here.
>>
Angus Blackbury - Fri, 30 Sep 2016 21:04:04 EST ID:sWygU/VW No.15233 Ignore Report Quick Reply
>>15231
OP high as fuck


Basic trig question by Geraldo juarez - Tue, 13 Sep 2016 14:35:19 EST ID:wFiRC6TB No.15197 Ignore Report Reply Quick Reply
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Ok so long story short - my math teacher this semester is the wort teacher ive ever had in my entire life. Asked him what formula they used to cme up with the xy coordinates on a unit circle. Example: terminal leg of 45* aka pi/4 on the unit circle intercepts at p=(root2/2, root2/2). He said there is no formula you just have to memorize. Are you kidding me i studied the chapter over and over and realized its the pythagorean theorum no matter what the radius equals. What a shit teacher.

Anyway my question is how does sin=y, but the fundamental idenitity of sin is 1/csc? Does this mean that y=1/csc?
Part 2: can that one be interchanged with any value of r? For example does it apply for circles that are not unit circles?

I know this is super basic, and my book explains it in a complex way, but its not like i have a good enough teacher to ask any questions to fill in the holes. Ive had straight a's and b's in my previous classes up til this guy.
5 posts and 3 images omitted. Click Reply to view.
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Vesuvius - Sat, 17 Sep 2016 11:24:58 EST ID:9fX9//hV No.15203 Ignore Report Quick Reply
>>15202
it's like asking why do we call dogs, dogs? Because that's just what we call them.
>>
John Bundlefoot - Sun, 18 Sep 2016 04:18:43 EST ID:9fX9//hV No.15205 Ignore Report Quick Reply
>>15204
I should say the same to you.
>>
John Bundlefoot - Sun, 18 Sep 2016 04:20:21 EST ID:9fX9//hV No.15206 Ignore Report Quick Reply
>>15204
I never said I didn't understand the post. I said you were overcomplicating it. If you don't understand the difference you probably shouldn't be giving people advice about anything.


Sett theory by Graham Fingerhat - Thu, 01 Sep 2016 05:16:48 EST ID:NsqdJ6Lc No.15184 Ignore Report Reply Quick Reply
File: 1472721408300.jpg -(2195808B / 2.09MB, 3920x2204) Thumbnail displayed, click image for full size. 2195808
Is there a way to find the equivalence relation corresponding to any partition?
Like p = {{1,4,7},{2,5,8},{3,6},{9}} with is an example i have in front of my nose. Can I find the relation from wich i get that partition of {1,2,3,4,5,6,7,8,9} ?
For the record I think not, but I only read about this stuff last night.
5 posts and 1 images omitted. Click Reply to view.
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Charlotte Gobberhood - Tue, 06 Sep 2016 18:06:06 EST ID:4JPlB6jB No.15190 Ignore Report Quick Reply
>>15186
>This is the same as having that b in P_i and a in P_i, so (b,a) in R, so the relation R is reflexive.
This should say symmetric at the end instead of reflexive.

>>15187
>manually define an equivalence
Do you mean the realtion induced by a partition or something else? I'm not sure what constitutes "manually" defining a relation. Also, it's not rigorous to say that
>numbers are in the equivalence class here if they are 3 more than some other number in the equilance class
since the partition {{1,4,7},{2,5,8},{3,6,8}} also has that property and induces a different equivalence relation.
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Charlotte Gobberhood - Tue, 06 Sep 2016 18:07:01 EST ID:4JPlB6jB No.15191 Ignore Report Quick Reply
>>15190
>{{1,4,7},{2,5,8},{3,6,8}}
This should be {{1,4,7},{2,5,8},{3,6,9}} obviously.
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Nathaniel Fembledatch - Wed, 07 Sep 2016 18:46:55 EST ID:DsqbErs4 No.15193 Ignore Report Quick Reply
>>15190

Oh I misread the OP, you're right. What I mean by manually defining an equivalence is to identify all the elements of one of partition sets. You could rephrase what I said by identifying the orbits of the action of adding 3 to elements of the set, with the caveat that 9 is in its own equivalence class separate from everyone else.


A Geometry(?) Question by Henry Bugglewill - Thu, 31 Mar 2016 20:43:14 EST ID:Z131bdYa No.15075 Ignore Report Reply Quick Reply
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What is the mathematical/geometric name for the shape of a peanut butter cup like this?

The best I can come up with is "crennelated truncated cone" but I feel like there's some ten-word name I could use that would very accurately describe it....
6 posts and 2 images omitted. Click Reply to view.
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Molly Suvingham - Tue, 19 Apr 2016 21:39:48 EST ID:dFkJK1jc No.15096 Ignore Report Quick Reply
should call it the Reese Cup. if anyone's qualified to name it it's us
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Nell Penderfedging - Sun, 15 May 2016 20:38:08 EST ID:1eeqYqTy No.15117 Ignore Report Quick Reply
>>15075
Upside down star fort.
>>
John Funkinshaw - Thu, 25 Aug 2016 10:53:32 EST ID:n7MnP1ar No.15182 Ignore Report Quick Reply
>>15075
crennelated frustum


Probability question (probably beneath most you) by Esther Dirringlore - Mon, 16 Nov 2015 07:50:43 EST ID:TdrCDJzk No.14973 Ignore Report Reply Quick Reply
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I'd appreciate it if someone could answer a probability question for me. I can't remember exactly how to work it out.

Question: How many combinations of 3As and 5Bs are there? For example, one combination would be: 'AAABBBBB' ; another would be 'ABABABBB'.
3 posts omitted. Click Reply to view.
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Lillian Povingstone - Tue, 17 Nov 2015 01:03:27 EST ID:TdrCDJzk No.14977 Ignore Report Quick Reply
>>14973
Okay. Ignore this thread. I found an online combinations calculator.
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Whitey Gobbleson - Tue, 17 Nov 2015 14:30:55 EST ID:J4OUpAxW No.14978 Ignore Report Quick Reply
>>14977
Magnets how do they work?
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John Divingmetch - Tue, 23 Aug 2016 13:31:10 EST ID:TANb9lmN No.15181 Ignore Report Quick Reply
8!/(3!*5!)


Help me help someone get a math-boner by Hannah Sollernodge - Fri, 22 Apr 2016 13:02:27 EST ID:WD6PkLOh No.15100 Ignore Report Reply Quick Reply
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Ok, so how would you introduce someone to the fun bits of mathematics? My girlfriend has maths at standard grade (8/9th grade for Americans I think), and she's interested in seeing why I do it just for fun. She isn't too patient with it, I tried to explain that x^1/3 is the cube root of x and she just got angry after a while and quit, so it needs to have the most 'wow' for the least amount of difficulty (basically math porn). I was going to show her some very basic calculus and some quadratic equation shit, but I'm doubting myself now.
What should I be showing her, or is it a lost cause?
13 posts and 5 images omitted. Click Reply to view.
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Martin Goodfoot - Sun, 17 Jul 2016 21:20:51 EST ID:9K7KtQWq No.15177 Ignore Report Quick Reply
>>15100
explain what she enjoys in terms of math. Whenever I tell people you can explain biology/taxes/cooking in terms of math they get intrigued.
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George Gennerstock - Mon, 01 Aug 2016 12:05:29 EST ID:yxQzbAra No.15178 Ignore Report Quick Reply
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I have the same problem. I can't seem to be all that interested in mathematics. The only thing that serves as a motivation is when I solve a problem, which I see as moderate to hard, by myself. Too bad I am bad at maths, so that dopamine release doesn't happen a lot. I see the proposal of mixing maths with something you find genuinely interesting being mentioned. The only thing is, I find everything from astronomy and botany to politics and art interesting. I do not have many hobbies, because I usually lose interest in them after a period. I have brewed, planted, and written graffiti, but they never stick for more than a few projects.
How do I get myself interested in the amazing world of mathematics? I really want to be able to do complex equations one day. Is it really nothing else than forcing myself to do a few problems every day? I have the attention span of a pornstar's pubic hair, so I don't think that will work for me.
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Shit Benningbury - Sat, 06 Aug 2016 03:29:45 EST ID:ijd+nKqH No.15180 Ignore Report Quick Reply
Measurement by Lockhart
http://www.hup.harvard.edu/catalog.php?isbn=9780674057555

Here's Looking at Euclid by Bellos
http://www.alexbellos.com/numberland

Patterns of the Universe: A Coloring Adventure in Math and Beauty by Bellos
Find it on amazon, interesting math colouring book where you reveal patterns.

Loop, the game
http://www.loop-the-game.com/ Bellos also reinvented pool using an ellipse


Riddle your diddle by Archie Nemmerhock - Tue, 05 Apr 2016 18:49:37 EST ID:cTPi6AuQ No.15083 Ignore Report Reply Quick Reply
File: 1459896577222.gif -(2565092B / 2.45MB, 300x226) Thumbnail displayed, click image for full size. 2565092
There's two guys:
If guy #1 borrows 2 dollars from guy #2, they have the same amount.
If guy #2 borrows 2 dollars from guy #1. he has twice the amount of guy #1.
How much money do they have from the start?
3 posts and 1 images omitted. Click Reply to view.
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Phyllis Nivingshit - Mon, 11 Apr 2016 07:47:21 EST ID:A2j/BW/W No.15089 Ignore Report Quick Reply
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>>15086
Wow! Such math! So amaze! Wow!
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Phineas Condlenore - Sat, 07 May 2016 17:02:14 EST ID:3U6ZTH6i No.15114 Ignore Report Quick Reply
>>15086
Sooo.....
Lekta thought Phoebe was serious...

Lekta should be a cop.
>>
Priscilla Pinkinstone - Sat, 16 Jul 2016 01:31:09 EST ID:Tg2WbKCI No.15175 Ignore Report Quick Reply
>>15086
poor guy skipped reading comprehension class, wait that isn't real, you should still feel bad


Gamedev is great by Ian Dundleludging - Wed, 04 May 2016 00:31:32 EST ID:7yI2oiC+ No.15109 Ignore Report Reply Quick Reply
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it's a great way to see the impact of changes in your model. Of course this applies mostly to folks interested in applied mathematics. But what is "pure" mathematics, but math that hasn't been yet applied? Give me a physical interpretation of the fractional calculus. Better yet, show me it in a Game.

There's also the fact that a lot of gamedevs struggle with some basic maths, mostly stuff regarding linalg, quaternions come up a lot. You could probably help!

Did you know: There's a 420chan amateur gamedev community, >>>/vg/664016

And from a pedagogical pov, who'd bet against gamedev working its way into the classroom? It's the perfect confluence of any applied area you can think of, Fourier series to taxicab metric
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Clara Fadgebit - Fri, 20 May 2016 17:24:26 EST ID:WHIrmu8h No.15127 Ignore Report Quick Reply
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> gamedev in the classroom

It would take the fun out of it eventually if it's forced. My first program was a game and later gamedev had me apply trig. It is still a lot of boring work, too, a lot of pure programming, so to speak, as pure maths is applied to maths.

Planning is required when fleshing out an game from scratch. There could be too much freedom in a project to grade it. Gamification works better if fit to the audience, eg. in a logic puzzle game.
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Ian Goodworth - Sat, 11 Jun 2016 17:23:59 EST ID:+Gs8DK3Y No.15159 Ignore Report Quick Reply
>>15127
True, making games is lots of programming and boring work until you get the interesting math part.

I think programming shaders is a better way of teaching maths https://www.youtube.com/watch?v=0ifChJ0nJfM
And to be honest most maths you will do in gamedev has to do with graphics.
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Shitting Crimmerfield - Mon, 20 Jun 2016 01:47:59 EST ID:ZiObD4pn No.15173 Ignore Report Quick Reply
>>15159
Maybe gamedev isn't that good for applying maths, but I'm pretty sure it's good for making physics simulations.


How do I recover the signs of integrals and derivatives? by Nell Penderfedging - Sun, 15 May 2016 20:44:52 EST ID:1eeqYqTy No.15118 Ignore Report Reply Quick Reply
File: 1463359492478.png -(46691B / 45.60KB, 787x421) Thumbnail displayed, click image for full size. 46691
I can define derivatives and integrals in terms of the Lebesgue
measure but how do I recover signs?

$$ \left. \left\lvert \frac{\mathrm{d} y}{\mathrm{d} x} \right\rvert \right\rvert_{x = a}=
\lim_{C \rightarrow \left\{a\right\}}\frac{\lambda^*\left( \left\{ y_x \, \vert \, x \in C \right\} \right)}{\lambda^*\left( C \right)} $$

$$ \left\lvert \, \underset{\, \, x \in C}{\int} y \, \mathrm{d} x \right\rvert =
\lambda^* \left( \left\{ \left( x , y_x \right) \, \vert \, x \in C \right\} \right) $$
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Martha Pudgestedging - Tue, 14 Jun 2016 12:22:55 EST ID:c7Q4EFJt No.15163 Ignore Report Quick Reply
So there's two ways to do this. The first is to define the integral in terms of the lebesgue measure and use the doublet distribution to define the derivative in terms of an integral transform and the second is to define a delta as the lebesgue measure of the increasing sections of a function minus the measure of the decreasing sections of a function and then define the derivative using the delta as normal.


Mathemusings by Betsy Puffingspear - Wed, 08 Jun 2016 18:56:24 EST ID:3U6ZTH6i No.15153 Ignore Report Reply Quick Reply
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Hey, I thought this board would appreciate this question the most.

So you lightly press your fingers on a string to play the harmonic.
(I'm gonna pretend i have a c-string on my guitar because all the tables you will find lists c as the root note).

Lets say you play the 5th harmonic, lightly press 1/5 of the way from one end.
You hear an E, the 5/4 interval to C
The 3rd harmonic, a G, the 3/2 interval

This could lead me to believe that if I play the 7th harmonic,
I would get the 7/6 interval, somewhere between D and D#

But I what i hear is something slightly lower than A# (or Bb if you will)

I'm thinking it's because 6 is not a square number.
Comment too long. Click here to view the full text.
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Hugh Sessledock - Thu, 09 Jun 2016 03:14:56 EST ID:lYjTKStM No.15154 Ignore Report Quick Reply
99% of modern instruments are tuned to equal temperament.
That means each half-tone is separated by adjacent ones by a ratio of 2^(1/12).

This also means that every interval (besides whole octaves) to an irrational number.
So when you go up/down musical intervals you end up precisely where you started if the number of steps up/down are the same. This however means through that notes will sound slightly off to natural notes.

I don't know if that answers you question:
https://en.wikipedia.org/wiki/Circle_of_fifths#Circle_closure_in_non-equal_tuning_systems
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Clara Grimridge - Thu, 09 Jun 2016 06:33:41 EST ID:3U6ZTH6i No.15155 Ignore Report Quick Reply
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>>15154
Well aware of the equal temperament thing.
I also know that the 1/7 harmonic is not used in most Just Intonation tunings.
I'm talking about the actual harmonic to interval relation.
I kinda expected the 7/6 interval, 7 being the root note (the whole string) and 6 being the note I hear from pinching that whole string 1/7 of the way from the end.
(6/7 of the way from the other end ofc)
What I hear is closer to a 16/9 interval (I think it's slightly lower)

I'm pretty sure it's because six times a seventh does not produce an octave of a seventh, like a square number would.

Still I am unable to form a good theory of what's happening.
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James Trotman - Tue, 14 Jun 2016 16:46:24 EST ID:3U6ZTH6i No.15164 Ignore Report Quick Reply
1465937184594.jpg -(13970B / 13.64KB, 394x467) Thumbnail displayed, click image for full size.
Well if anyone cares, I figured it out to my satisfaction.
4 being the closest square number; 4 sevenths of the string, bringing out the 7/4 interval of C, the flat Bb; is the one ringing out the most when I pinch a seventh.
Was pretty obvious in hindsight. nb.


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