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Calculating Combinations by Augustus Gennerson - Sun, 28 Apr 2013 03:08:31 EST ID:GaVlYA/B
1367132911098.jpg -(68401 B, 834x555) Thumbnail displayed, click image for full size.
Hi /math/, I haven't done any in a long time, so I'm hoping someone will pity me and offer assistance. I am trying to figure out how many possible combinations there are for a team of 12 players, in which the games only have 3 play per match.

I have the dumb, so all I know is 12/4=3, and 12/3=4, and 3*4=12, and 4*3=12 and blah blah multiples, lowest common denominator blah blah.

How does I calculate this?
1 posts omitted. Click Reply to view.
 >> Emma Denderwodge - Sun, 28 Apr 2013 17:13:41 EST ID:MTIV7/tU Ignore Report Quick Reply >>11461And that's 220, if you don't know binomials.
 >> Doris Nugglefit - Wed, 08 May 2013 11:18:37 EST ID:F9AJX/Os Ignore Report Quick Reply >>11463and thats 11011100 in binary, if you don't know the decimal system
 >> Shitting Fuckingwell - Wed, 08 May 2013 12:09:13 EST ID:X70kgTC4 Ignore Report Quick Reply 1368029353502.gif -(2085214 B, 300x169) Thumbnail displayed, click image for full size. >>115481101110
 >> Shitting Fuckingwell - Wed, 08 May 2013 12:16:00 EST ID:X70kgTC4 Ignore Report Quick Reply >>11549Disregard this. I don't even.
 >> vibram five finger - Sat, 25 May 2013 19:00:09 EST ID:zImyfOsU Ignore Report Quick Reply Calculating Combinations - Mathematics - 420chan vibram five finger http://www.vibraminfivefingers.com/

Proof by contradiction by Phyllis Nembleput - Mon, 14 Jan 2013 12:57:17 EST ID:RXvx7dga
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When using proof by contradiction, instead of using algebra to prove the converse of your original statement to be contradictory, could I just use a numerical example to show the converse is a contradiction? I can do the former but with some examples the latter takes all of 20 seconds in an exam and I don't recall my lecturer saying anything about it/putting it in the class notes.
5 posts and 1 images omitted. Click Reply to view.
 >> Ms Glove !vB6hfWdIKU - Tue, 15 Jan 2013 13:19:12 EST ID:jPdzCuJW Ignore Report Quick Reply >>10749I don't think you are mad. The function is not a bijection because it's not surjective. The function doesn't give values for (0,1) in Q\{0}.
 >> Sidney Dizzlegold - Tue, 07 May 2013 16:58:31 EST ID:MTIV7/tU Ignore Report Quick Reply >>10742Isn't what you're talking about just a counter-example? If then it works, of course. If not, I don't get what you're saying.>>10747There should be one, both sets are infinite and countable.Since a monotonic bijection exists between Z and Z\{0}, I assume there has to be one between Q and Q\{0}.
 >> Priscilla Turveyhood - Thu, 09 May 2013 00:34:02 EST ID:Z8arPLrB Ignore Report Quick Reply if you have a proposition P(n) and you show that the converse P^-1(n) is not true for some n, that does not prove the original proposition.
 >> chanel handbags - Fri, 24 May 2013 20:53:20 EST ID:rEpQn0hX Ignore Report Quick Reply Proof by contradiction - Mathematics - 420chan
 >> MULBERRY BAGS - Sat, 25 May 2013 18:36:45 EST ID:Vkrure+p Ignore Report Quick Reply Proof by contradiction - Mathematics - 420chan

Frequency discussion by Frederick Guttingchatch - Thu, 23 May 2013 06:25:17 EST ID:uX1TaQqB
1369304717182.jpg -(1080121 B, 1621x1691) Thumbnail displayed, click image for full size.
Hey /math/, I think this stuff is right down your alley. I'd like to have as many educated opinions on this matter as possible so we can get to the bottom of the array of possibilities this theory promises.
There's not a whole lot of discussion anywhere else on the Internet, there's only a handful of books being published on the whole deal.
So before you read the thread on /mu/ I'll tell you that it's all based on the evidence of 528 hz being the naturally occurring frequency that governs life.
So please, help me make sense of this stuff like I know you guys can!
http://boards.420chan.org/m/res/401742.php
>Pic related, it's what the theory is mathematically based on.
2 posts omitted. Click Reply to view.
 >> Cyril Goodshaw - Thu, 23 May 2013 10:11:24 EST ID:g9W50kA4 Ignore Report Quick Reply >>11724Yes, numerology is always nonsense. The only use reasonable people have for numerology is to have a fun way to play with numbers. By that, i don't mean "determine the true name of God using some alphanumeric code, a 6 sided die, the Bible, and a bucket of alphabet soup." I mean just playing with numbers in silly ways just to play with numbers.Example of a healthy game: raise a number to the power of the preceding number. example: 1^0=1, 2^1=2, 3^2=9, 4^3=64There's no magic there, no mysticism, just a mental exercise.Or let's play a game with the "ultimate/divine number" 12 there are countless "divine" numbers because there aren't really any and you New Age whackos are some crazy and gullible bastards 12 is the best number because it starts with one, then proceeds to 2. 1 and 2 are next to each other, so just add them and you get 3. divide 12 by the sum of its digits, and you get 4. See how easy it is to get 1,2,3,4 out of 12? it must be magic, because i performed some abstract process to it (summation of the component digits). A reasonable person, if they liked numbers and math, would say "haha, that's neat, how far and abstract can we go with the number 12 and standard math operations? maybe fiddle with what number base we use?"A numerologist would say "IT PROVES MAGIC IS REAL BECAUSE I USED A PLUS SIGN!"
 >> John Hagglechan - Thu, 23 May 2013 14:35:21 EST ID:sPd/0oB/ Ignore Report Quick Reply >So please, help me make sense of this stuff like I know you guys can!There are no sense to make here. You'll eventually make your own if you try hard enough: that's what numerology is all about. This guy >>11723 is right.You'll get zero help from this forum because we're actual wannabe scientists and we like facts.Try /tinfoil/ instead.I'd love to be proved wrong. But you didn't said anything substantial in your post so there are nothing to prove or disprove.
 >> Nell Blillerdot - Thu, 23 May 2013 22:42:01 EST ID:v+f/iPwQ Ignore Report Quick Reply how don't you idiots get it? 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 = 45 = 4 + 5 = 9 it's all about 9 so if I wrap some write around a torus 999999999 times it will create a time warp device that gives infinite free energy and cures cancer
 >> Jenny Duckford - Fri, 24 May 2013 06:18:58 EST ID:MTIV7/tU Ignore Report Quick Reply >>11737This guy gets it.
 >> Edward Bunbanks - Sat, 25 May 2013 15:39:11 EST ID:Dn4zhXKX Ignore Report Quick Reply There's an observation made by Richard Guy called the "Strong Law of Small Numbers":"There aren't enough small numbers to meet the many demands made of them."There's a multitude of properties, relationships, and operations we can define upon numbers, but when you cram them into the space of 1 - 10, or 1 - 100, or 1 to Skewe's number, you don't have enough wiggle room to say that coincidences are anything more.This "Strong Law" furnishes a lot of numerology (but also some surprising reversals in number theory, in that numbers don't reach "typical behavior" until they get very very big).His paper contains a lot of these (>>11725) "games"mathdl.maa.org/images/upload_library/22/Ford/Guy697-712.pdf

Refresher course by Albert Blubbletick - Thu, 23 May 2013 20:15:28 EST ID:oZ/BYnFU
1369354528919.jpg -(434609 B, 3000x2169) Thumbnail displayed, click image for full size.
Can you fine people recommend a user-friendly source to brush up on math?

I haven't studied it since undergrad about 6 years ago and my skills are dull. i want to sharpen 'em up.

Please no algebra or calculus, I'm talking basic applicable mathematics.

Thanks, enjoy pic
 >> Graham Pirryhere - Fri, 24 May 2013 23:42:34 EST ID:vBgvihT5 Ignore Report Quick Reply >>11736>no algebra>basic mathFucking pre-algebra is as basic as it gets you ape
 >> Eugene Gindleforth - Sat, 25 May 2013 09:26:21 EST ID:Jb2ZUqsJ Ignore Report Quick Reply >>11744Whoa dude chill. You make this board look like a bunch of elitist assholes.OP, calculus and good arithmetic is absolutely necessary for stuff like Physics and Chemistry. If you want other mathematics for different applications, you should mention specifically what it is.I don't have any links for you, sorry, but khan academy gets mentioned a lot around here. I don't know if it is good for refreshing your skills, but it is worth a try.Best of luck.

Out of kilter algorithm by Phoebe Clollerwere - Thu, 04 Apr 2013 22:49:27 EST ID:pagK+41n
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Hey, anybody here had the doubtful pleasure of using the out of kilter algorithm (for minimum cost flow problem)?
 >> BUY WOW GOLD - Fri, 24 May 2013 19:08:49 EST ID:Sqeb9aC5 Ignore Report Quick Reply Out of kilter algorithm - Mathematics - 420chan
 >> CHRISTIAN LOUBOUTIN SHOES - Sat, 25 May 2013 05:54:47 EST ID:d3xvcZKr Ignore Report Quick Reply Out of kilter algorithm - Mathematics - 420chan

Solve for P by Wesley Pittway - Sun, 19 May 2013 13:45:42 EST ID:MHkE3Ne7
1368985542087.png -(8058 B, 367x105) Thumbnail displayed, click image for full size.
Values for all variables (including Pe) apart from P are known. How do I solve for P?
3 posts omitted. Click Reply to view.
 >> Ernest Pittson - Sun, 19 May 2013 16:26:30 EST ID:cZ4A6U3z Ignore Report Quick Reply Numerically. nb because this is entirely unhelpful.
 >> Wesley Pittway - Sun, 19 May 2013 16:41:31 EST ID:MHkE3Ne7 Ignore Report Quick Reply >>116801/cos
 >> Martin Wiblingbidge - Mon, 20 May 2013 09:06:44 EST ID:DGmXZ4mU Ignore Report Quick Reply >>11682I'd say numerically too, then.
 >> Phineas Duddleforth - Thu, 23 May 2013 22:56:00 EST ID:6nOiqmT1 Ignore Report Quick Reply >>11677umm just use arccosThis is totally solvable with rearranging the variables and arccos.
 >> Thomas Mummlekug - Fri, 24 May 2013 15:23:16 EST ID:wEoAa4+Y Ignore Report Quick Reply >>11738Oh shit jolly african-american what are you doing

Want to learn math on my own by Nathaniel Ballerwell - Thu, 23 May 2013 19:39:22 EST ID:nLSaoWdR
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I want to start studying math on my own.

The thing is that I finished highschool a while ago and where I live you choose between different orientations based on what you want to study on college and that's what you learn on the last years of highschool. I chose something mostly based for people who are going to law school and we didn't have math at all. So I know shit about math and I think I don't remember much from the first years of highschool.

I'm thinking of going to khanacademy and studying from the very beginning. Any other resource you think may help me?

Graph the radius of a square. by Dogfeet - Thu, 16 May 2013 17:13:51 EST ID:XQCSWhl+
1368738831516.png -(16757 B, 761x404) Thumbnail displayed, click image for full size.
An 8x8 square.

If we think of the line from the center of a square to its outer edge as the square's radius, then we recognize that the radius changes from a minR of 4 (to any side) to a maxR of √32 (to any corner). Then we realize, similar to the unit circle, that the radius starts at 4 at 0° and returns to 4 at 90°, 180°, and 270° before coming back to 0° or 360° depending on how you look at it. Now, if we took this "circle" and made it a sine wave, the period would be 1/4 of the normal period because we're measuring the amount of times the radius returns to minR.
>sin(4x)
Now we need to find the amplitude. This would be maxR-minR or √32 - 4.
>(√32 - 4)sin(4x)
And the center line of the sine wave needs to be directly between minR and maxR, so 4+1/2(√32 - 4)
>( [√32] - 4)sin(4x)+4+1/2(√32 - 4)
But wait. We want the wave to start at 4 and go up to √32. So we need a negative cosine wave. And that means we need to change the starting point to 4.
> -( [√32] - 4)cos(4x)+4

Right?
7 posts omitted. Click Reply to view.
 >> Dogfeet - Tue, 21 May 2013 15:58:54 EST ID:XQCSWhl+ Ignore Report Quick Reply >>11685Well, yeah. But I don't really see it as an issue.
 >> Mr Smells - Wed, 22 May 2013 19:37:21 EST ID:dhANKuZP Ignore Report Quick Reply >>11698The issue is that your graph doesnt have 4 as its min
 >> Dogfeet - Wed, 22 May 2013 20:18:36 EST ID:XQCSWhl+ Ignore Report Quick Reply >>11711Woooooops. Sorry about that. Guess I made a mistake somewhere up there.
 >> Dogfeet - Wed, 22 May 2013 20:20:45 EST ID:XQCSWhl+ Ignore Report Quick Reply >>11712The last number in the equation shouldn't be a 4, it should be 4+1/2(√32 - 4).
 >> George Dillerfoot - Thu, 23 May 2013 19:20:22 EST ID:gmpe3Fqt Ignore Report Quick Reply $y=\frac{\left(\sqrt{32}-4\right)}{2}\sin \left(4x-\frac{\pi }{2}\right)+4.8284271$all else is for fags

The addiction.. by Emma Porringmadge - Wed, 10 Oct 2012 23:19:25 EST ID:1f3KRE9q
1349925565547.jpg -(55399 B, 400x300) Thumbnail displayed, click image for full size.
DICKS EVERYWHERE
7 posts and 2 images omitted. Click Reply to view.
 >> Clear !U5Lofz42s2 - Sat, 16 Mar 2013 13:54:15 EST ID:Za8gbo3B Ignore Report Quick Reply >>10231
 >> Jarvis Cublingsotch - Fri, 12 Apr 2013 18:17:10 EST ID:vFs0EWS3 Ignore Report Quick Reply 1365805030477.jpg -(62383 B, 640x380) Thumbnail displayed, click image for full size. i swear someone keeps bumping this thread
 >> Emma Drezzlesudge - Fri, 12 Apr 2013 22:10:55 EST ID:F9AJX/Os Ignore Report Quick Reply >>11335thank GOD im not the only person who noticed that. i thought i was crazy hahaha
 >> Eliza Hellerled - Sat, 13 Apr 2013 03:19:03 EST ID:im+4kU6z Ignore Report Quick Reply >>11337it's the spam bots, kirt said they can't really move the threads back after deleting their posts
 >> Graham Crommerstune - Sat, 13 Apr 2013 12:28:40 EST ID:UFKy19qo Ignore Report Quick Reply 1365870520241.jpg -(24848 B, 300x300) Thumbnail displayed, click image for full size. >>11335DAT RATIO

calc by Sophie Huddledock - Thu, 23 May 2013 00:44:27 EST ID:Qa+J3W9v
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I just finished my second calculus 1 class of my seven week summer course. We finished up limits entirely and started derivatives, and i'm really enjoying it so far. I am really scared for the rest of the course though seeing as its such a short amount of time to do everything. Should i be worried, or with enough practice can anyone succeed in calc?
 >> Martha Ponderdale - Thu, 23 May 2013 05:52:37 EST ID:MTIV7/tU Ignore Report Quick Reply >>11714If you're enthusiastic about it, then I don't think you'll have too many problems. That's the most important part.
 >> Dogfeet - Thu, 23 May 2013 05:59:14 EST ID:XQCSWhl+ Ignore Report Quick Reply >>11714The biggest part of Calc is just remembering how to do it. If you need to study, study like there's no tomorrow. I never really needed to study to remember things, but I definitely studied for my Calc exam. Other than that, it's not really so hard. Good luck.

Euler's Identity by Bane El-Shaqqid - Fri, 17 May 2013 01:28:59 EST ID:j3UCMCHC
1368768539135.jpg -(48289 B, 400x316) Thumbnail displayed, click image for full size.
It's the most beautiful equation in all of math?
Big deal.
I'm not a mathematician, and I do not get why mathists jizz themselves over it.
i apologize for offending anyone
1 posts omitted. Click Reply to view.
 >> Henry Weshstone - Fri, 17 May 2013 03:18:04 EST ID:pkC9MHtb Ignore Report Quick Reply It's the only formula that includes all the basic numbers. I don't know how this is useful though. Hopefully someone will explain
 >> Thomas Lightham - Fri, 17 May 2013 08:47:55 EST ID:gxGOnLrS Ignore Report Quick Reply 1368794875540.png -(4956 B, 331x65) Thumbnail displayed, click image for full size. The proof showing how it is true is not that hard or gracious, and it isn't more useful than the general formula (pic related). What is important in the eyes of mathematicians is the simplicity of the formula, that uses really important numbers from different fields of mathematics. Mathematics isn't about usefulness, it's more about the deep relations between the abstract notions, and Euler's identity is the perfect example of that, and this is what we call gracious.
 >> Thomas Lightham - Fri, 17 May 2013 08:49:27 EST ID:gxGOnLrS Ignore Report Quick Reply >>11663Oops, scratch the \pi in the pic, it's not supposed to be here.
 >> Esther Honeylock - Fri, 17 May 2013 16:28:24 EST ID:sPd/0oB/ Ignore Report Quick Reply Just look at it. LOOK AT IT FFS>e^pi*i = -1What the fuck? You throw an exponential, pi and i in the same formula... And the result is still -1 ?In the real set, there are no apparent connections between exponential and pi. In fact, e^pi = 23.14069...Yet here it is, a clean and really simple relation between the 3 most used constants.That's where the complex set and the imaginary unit shine.
 >> Emma Mundlelock - Sat, 18 May 2013 20:41:05 EST ID:x7U2sRt1 Ignore Report Quick Reply With it you can show that i^i is a real number, which is neat. Also since it's based in cos(x)+isin(x) it lets you convert nasty periodic functions in physics into terms of e^(ipix), which are very easy to work with.

calculus pls by Isabella Blibberstore - Sun, 12 May 2013 19:49:46 EST ID:Qa+J3W9v
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hey guys, I'm taking Calculus 1 this summer for a seven week course. I have taken pre calc last semester but i'm still kind of scared because of what everyone says about the classes difficulty. Whats the best way i can prepare myself?
1 posts omitted. Click Reply to view.
 >> Alice Carringridge - Sun, 12 May 2013 22:03:04 EST ID:F9AJX/Os Ignore Report Quick Reply just do a lot of algebra problems with various functions. understand what a function is. make doing algebra second nature.then youll be able to handle the ideas in calc 1 well, its basically advanced algebra
 >> Martha Duckman - Mon, 13 May 2013 01:06:00 EST ID:Qa+J3W9v Ignore Report Quick Reply >>11620this did help a lot, thanks man ill check some of this stuff out online.>>11621ill review my algebra too thanks
 >> Reuben Cheblingcocke - Mon, 13 May 2013 17:21:05 EST ID:U15g+L7J Ignore Report Quick Reply calc isnt as hard as some people say it isi was super terrible at math all throughout high school and was forced to take pre-calc/calc in college. Just review your algebra
 >> Charles Honeybury - Thu, 16 May 2013 00:16:40 EST ID:zBQVxhDX Ignore Report Quick Reply From what I've seen, pre calc is one of the worst maths. I didn't take it at all and went straight from math AB or whatever to AP-Calc, with no issue.
 >> Augustus Sublingham - Thu, 16 May 2013 20:34:11 EST ID:4FNsadUJ Ignore Report Quick Reply So, in order to reduce your anxiety about your coming Calc 1 class this summer, you ask us how you can prepare?...How about you study?Google for a calc 1 textbook and start working through it.

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