## Search found 732 matches

- Sun Apr 20, 2014 9:00 am UTC
- Forum: Mathematics
- Topic: Estimators for attendance.
- Replies:
**3** - Views:
**2196**

### Re: Estimators for attendance.

Thank you both. If you're interested then here's some further context: I've recently taken over someone else's job and don't have too many of their old records. I don't know how heavily previous events were promoted (these are, by the way, non compulsory training events for long term volunteers) and...

- Fri Apr 18, 2014 2:26 pm UTC
- Forum: Mathematics
- Topic: Estimators for attendance.
- Replies:
**3** - Views:
**2196**

### Estimators for attendance.

So I'm organising an event and a lot of people aren't RSVPing very promptly but I do need to buy some refreshments etc so I am trying to make a guess for attendance based on who actually has gotten back to me. It's been a while since I did any maths and probability was never my forté but I got curio...

- Sun Jun 03, 2012 11:50 am UTC
- Forum: Mathematics
- Topic: Math: Fleeting Thoughts
- Replies:
**427** - Views:
**147257**

### Re: Math: Fleeting Thoughts

It's there a word to describe the smallest degree of polynomial to have a given number as it's root? So if it was f(x) then when x is a rational number, f(x) would be 1. f(sqrt(2))=2, f(pi)=infinity. I dunno if that would have any interesting properties or whatever but it feels like it should have a...

- Tue Jan 10, 2012 3:16 pm UTC
- Forum: Fit Club
- Topic: How to decide on targets and questions to ask a trainer.
- Replies:
**2** - Views:
**2306**

### How to decide on targets and questions to ask a trainer.

I joined a gym on Saturday (new years cliche, I know), and membership came with one free personal trainer session. I wasn't going to use that free session for a while but a personal trainer approached me yesterday while I was staring at a resistance machine looking confused and before I knew it I ha...

- Wed Nov 30, 2011 2:55 pm UTC
- Forum: Mathematics
- Topic: Simultaneous equations
- Replies:
**1** - Views:
**690**

### Re: Simultaneous equations

Yeah they're called simultaneous equations. And yes that's gotten you a correct answer. (although it took me a minute to realise that the 1 and 2 and the end of each wasn't part of the equations, typically you'd put those in brackets or something to avoid ambiguity). Another way you could have done ...

- Fri Jul 08, 2011 9:20 am UTC
- Forum: Mathematics
- Topic: How difficult is Discrete Mathematics?
- Replies:
**23** - Views:
**13937**

### Re: How difficult is Discrete Mathematics?

Most of that looks kind of well, essential for any course really: learning how to do proofs in discrete is a pretty good stepping stone to being able to do proofs in real analysis. You need set theory basically all the time (there is not actually such thing as set theory, there's just a lot of termi...

- Mon Mar 14, 2011 10:27 pm UTC
- Forum: Mathematics
- Topic: [0,1] ~ [0,1) (Cardinality)
- Replies:
**5** - Views:
**3988**

### Re: [0,1] ~ [0,1) (Cardinality)

I asked my teacher and he told me that I should find an injection from each to the other, as that guarantees they are equipotent. Where can I find a proof of that theorem? It's called the Cantor–Bernstein–Schroeder Theorem , the Wikipedia article is okay. Can I still find a bijection which is not h...

- Thu Mar 10, 2011 11:43 am UTC
- Forum: Mathematics
- Topic: Four nines puzzle
- Replies:
**13** - Views:
**3049**

### Re: Four nines puzzle

Urm... it was one in the morning? Does that count as an excuse?OverBored wrote:the tree wrote:4 = 2!

- Thu Mar 10, 2011 12:48 am UTC
- Forum: Mathematics
- Topic: Four nines puzzle
- Replies:
**13** - Views:
**3049**

### Re: Four nines puzzle

Okay. 1-12 Assume 1 is to be read as .9(bar) 1 = 99/99 2 = 9/9 + 9/9 3 = (9 + 9 + 9)/9 4 = 2! 5 = 9.9(bar)/(1 + 1)) 6 = 3! 7 = (9 - 1 -1)/1 8 = (9 - 1) * 1 * 1 9 = 9 * 1 * 1 * 1 10 = 9.9(bar)*1*1 11 = (9.9(bar)+1)*1 12 = 9.9...

- Mon Feb 28, 2011 1:15 am UTC
- Forum: Mathematics
- Topic: |i|
- Replies:
**34** - Views:
**5073**

### Re: |i|

You can think of absolute value in the real numbers as the distance from 0. It's the same in the complex plane. I always like to go for "how 'big' a number is", which if you're thinking of complex numbers as vectors then that works quite neatly. Except that the imaginary numbers are not l...

- Mon Feb 21, 2011 5:38 pm UTC
- Forum: Mathematics
- Topic: |i|
- Replies:
**34** - Views:
**5073**

### Re: |i|

I always like to go for "how 'big' a number is", which if you're thinking of complex numbers as vectors then that works quite neatly.Meem1029 wrote: You can think of absolute value in the real numbers as the distance from 0. It's the same in the complex plane.

- Wed Feb 16, 2011 1:44 pm UTC
- Forum: Mathematics
- Topic: Is this a meaningless math question?
- Replies:
**24** - Views:
**2672**

### Re: Is this a meaningless math question?

Zero. Definitely zero.

- Wed Feb 16, 2011 11:52 am UTC
- Forum: Mathematics
- Topic: Is this a meaningless math question?
- Replies:
**24** - Views:
**2672**

### Re: Is this a meaningless math question?

EDIT: ok I think the probability thing is what is breaking everyones brainmeats.. :) would a more clearly defined question be "What percentage of natural numbers are prime?". The reason I was wondering if it were a meaningless question is because there are infinite natural numbers and als...

- Fri Feb 11, 2011 3:07 am UTC
- Forum: Mathematics
- Topic: The Tau Manifesto
- Replies:
**165** - Views:
**43564**

### Re: The Tau Manifesto

Everything is a 16th of something.doogly wrote: So clearly 45 degrees is "really" a 16th of something, right?

- Wed Feb 09, 2011 2:09 pm UTC
- Forum: Mathematics
- Topic: The Tau Manifesto
- Replies:
**165** - Views:
**43564**

### Re: The Tau Manifesto

While we're at it, [imath]8\pi = \frac{\pi}{0}=0.999\dots = i = -i = \aleph_\frac{1}{2}[/imath] as well - it couldn't hurt.

- Fri Feb 04, 2011 4:30 pm UTC
- Forum: Mathematics
- Topic: How should I get into 'higher' mathematics?
- Replies:
**11** - Views:
**1763**

### Re: How should I get into 'higher' mathematics?

Presumably you're doing some sort of precalculus or algebra or whatever you're calling it at the moment and you're only just being properly introduced to polynomials. As it happens, polynomials are kind of really really important when it comes to nearly the rest of mathematics. Learn to factor them,...

- Wed Jan 26, 2011 10:51 am UTC
- Forum: Mathematics
- Topic: ridiculous naming trend in definitions
- Replies:
**18** - Views:
**3045**

- Tue Jan 25, 2011 1:59 pm UTC
- Forum: Mathematics
- Topic: ridiculous naming trend in definitions
- Replies:
**18** - Views:
**3045**

### Re: ridiculous naming trend in definitions

It seems that there is no end to the amount of different "[adjective] numbers". Integers can be happy, amicable, friendly, sexy, perfect...

- Mon Jan 17, 2011 12:24 pm UTC
- Forum: Mathematics
- Topic: functions that give cool designs
- Replies:
**56** - Views:
**17639**

### Re: functions that gives cool designs.

Case in point, if OP had just asked his classmates what some cool linear equations were, he'd never have discovered that implicit or parametric equations are more interesting. Okay then... Afif_D : ⋅ If you really want to carry on with explicit functions then spend some time working on th...

- Sat Jan 15, 2011 1:43 pm UTC
- Forum: Mathematics
- Topic: functions that give cool designs
- Replies:
**56** - Views:
**17639**

### Re: functions that give cool designs

I'm already fairly sure of what it'll turn out to look like, based upon Qaanol's post.

- Wed Jan 12, 2011 4:26 pm UTC
- Forum: Mathematics
- Topic: functions that give cool designs
- Replies:
**56** - Views:
**17639**

### Re: functions that gives cool designs.

Try urm... y^2 = \sin(2 \pi x^n) for any natural n, that's a fairly pleasant set of blobby things, I'm fairly sure that the area enclosed by the blobby things is always infinite but don't hold me to that. I thought you all genius guys would pt some cool functions in here.... but i was wrong....

- Fri Dec 31, 2010 3:29 pm UTC
- Forum: Mathematics
- Topic: Questions about sets
- Replies:
**18** - Views:
**3037**

### Re: Questions about sets

\aleph_{0} is defined as the smallest infinite cardinal, \aleph_{1} is defined as the second-smallest, \aleph_{2} is the third smallest, etc. Considering cardinalities is something we really don't know much about (or so I'm told) - what happens if it turns out that between any two cardinalities, th...

- Fri Dec 17, 2010 2:48 am UTC
- Forum: Mathematics
- Topic: Useless Math
- Replies:
**60** - Views:
**9787**

### Re: Useless Math

Pretty wrong, yeah. For instance, I'm doing coding theory at the moment, which is largely in an arbitrary amount of dimensions.ImTestingSleeping wrote:I would think that mathematics in higher dimensions would be rather useless. Would I be wrong with that statement?

- Sat Dec 11, 2010 10:37 am UTC
- Forum: News & Articles
- Topic: Britain increases tuition, met with violent protests
- Replies:
**148** - Views:
**12484**

### Re: Britain increases tuition, met with violent protests

For the record - the protests were not just about the fees increase, but the funds decrease that comes with it. Not to mention the EMA 're-structuring', which is of course going to get a lot more people a lot more angry as the vote on that comes up. It's for this reason that I'm writing this from wi...

- Mon Dec 06, 2010 3:53 pm UTC
- Forum: Mathematics
- Topic: Probability of finding two snowflakes alike? Need help!
- Replies:
**7** - Views:
**3353**

### Re: Probability of finding two snowflakes alike? Need help!

Really the question is how many ways can [however many] water molecules be arranged in a snowflake like pattern, which requires knowing more about water molecules than it does about probability.

- Mon Dec 06, 2010 3:19 pm UTC
- Forum: Mathematics
- Topic: Polar Coordinates Intuition
- Replies:
**7** - Views:
**1555**

### Re: Polar Coordinates Intuition

If you're plotting an explicit function, and I say plotting rather than sketching, a table of values is really all you're aiming for.cba wrote:That annoyed me becasue i quite like graphing in a normal x-y co-ordinate system, where doing a table of values really doesnt help you at all...

- Sun Dec 05, 2010 10:03 pm UTC
- Forum: Mathematics
- Topic: Polar Coordinates Intuition
- Replies:
**7** - Views:
**1555**

### Re: Polar Coordinates Intuition

So how do I develop the intuition for visualizing the graph of a polar function in my mind? Are there any tricks to it or any general forms to memorize? I can't really think of any. I just think, what is r when theta is 0 and when you deviate from zero the left or the right - how does r change. Sim...

### Re: This.

It's really not specific to these fora, I've seen it generally across the Internet. Lots of forum software has a feature that every post must contain at least some characters, and those within quote tags don't count so things like "this", "QFT" or "^^^^" below a quote a...

- Wed Dec 01, 2010 11:43 am UTC
- Forum: Science
- Topic: Rate of change for a charging battery.
- Replies:
**2** - Views:
**474**

### Rate of change for a charging battery.

(maybe this should have been put in Fleeting Thoughts - but the Science one of that is old and empty so I figured it wouldn't hurt to create a new thread) I noticed that when charging my phone, it seems to slow down as it gets closer to 100%, that is that it gets from 0 to 50% in a few minutes but t...

- Thu Nov 25, 2010 5:15 pm UTC
- Forum: Mathematics
- Topic: Bessel functions.
- Replies:
**1** - Views:
**538**

### Bessel functions.

(this is for uni, so I guess it counts as homework help) I've only just come across these functions and suddenly I need to know how to work them, so please bear with me and my possibly kind of dumb questions. From what I've seen (reading from Advanced Engineering Mathematics, Kreyszig) Bessel's equa...

- Thu Nov 25, 2010 1:22 pm UTC
- Forum: Mathematics
- Topic: How hard is college level mathematics?
- Replies:
**36** - Views:
**9451**

### Re: How hard is college level mathematics?

I still get confused when Americans say college and they mean what you do after being 18. I'd say math/everything gets harder as it gets more specialised. Rather than just learning 'math' you will have many completely seperate classes , there's not much relation between an introduction to real analy...

- Wed Nov 24, 2010 5:01 pm UTC
- Forum: Mathematics
- Topic: LaTeX and other markup!
- Replies:
**73** - Views:
**35303**

### Re: LaTeX and other markup!

Thanks, eqn array managed to do it. (I had to spend a good bit of time staring at it to realise how to make that not ennumerate every line).

- Wed Nov 24, 2010 2:47 pm UTC
- Forum: Religious Wars
- Topic: Math or Science
- Replies:
**65** - Views:
**54056**

### Re: Math or Science

Since CS and programming is 99%+ mathematics, I vote that. Not only that. I think it's definitely worth noting that pure math is a thing which is why I outright reject the assertion that math is part of physics. I think this is beyond comparing apples and oranges, I think that trying to find a winn...

- Wed Nov 24, 2010 2:37 pm UTC
- Forum: Mathematics
- Topic: LaTeX and other markup!
- Replies:
**73** - Views:
**35303**

### Re: LaTeX and other markup!

Not sure if this the right thread to ask general LaTeX question but if anyone could help me with this, it'd be cool. In a document I'm writing I have: Some writing $ $ god awful equation that is a million billion characters long and makes you want to cry $ $ some more writing And within the double-d...

- Sun Nov 14, 2010 2:17 pm UTC
- Forum: News & Articles
- Topic: Some happier gay teen news
- Replies:
**8** - Views:
**2477**

### Re: Some happier gay teen news

How much of a problem is it that the Australian Christian Lobby can be dicks? Are they a powerful organisation?

- Fri Nov 12, 2010 1:50 pm UTC
- Forum: Individual XKCD Comic Threads
- Topic: 0818: "Illness"
- Replies:
**116** - Views:
**34871**

### Re: 0818: "Illness"

I am actually genuinely impressed that this, to the best of my knowledge, is the first update to be missed. It's like he's not even trying to be funny anymore. I think that was a little innapropriate, really. Obviously, no-one tries to be funny all the time, apart from douchebags who are a never fun...

- Fri Nov 12, 2010 1:38 pm UTC
- Forum: Science
- Topic: pseudoscience and quantum computers
- Replies:
**23** - Views:
**3226**

### Re: pseudoscience and quantum computers

Reckitt Benickiser, who make Finish cleaning products, has "Quantum", trademarked - so they can excuse it as just a brand. Like how Macintosh Computers, Wicked Lasers and Best Beer actually have nothing to do with coats [citation needed] , aren't evil and are meerly above par respectively....

- Thu Nov 11, 2010 10:12 pm UTC
- Forum: News & Articles
- Topic: Porpoises rescue Dick Van Dyke
- Replies:
**10** - Views:
**3520**

### Porpoises rescue Dick Van Dyke

The Guardian wrote:...the veteran star of Chitty Chitty Bang Bang and Mary Poppins had to rely on the help of a pod of porpoises after apparently dozing off aboard his surfboard...

...the porpoises were unavailable for comment...

I have nothing to add, I just think you all need to know that this happened.

- Thu Nov 11, 2010 8:20 pm UTC
- Forum: Mathematics
- Topic: HW Help: prove an element is primitive.
- Replies:
**16** - Views:
**1039**

- Thu Nov 11, 2010 8:09 pm UTC
- Forum: Mathematics
- Topic: HW Help: prove an element is primitive.
- Replies:
**16** - Views:
**1039**

### Re: HW Help: prove an element is primitive.

Make that five. Apparently all this mathsing it ruining my ability to count.

So okay, a penny has dropped, but possibly in the entirely wrong place - is it something to do with the elements can only have orders that are divisors of p-1? If so, does that urm... have a name I can look up or something?

So okay, a penny has dropped, but possibly in the entirely wrong place - is it something to do with the elements can only have orders that are divisors of p-1? If so, does that urm... have a name I can look up or something?