Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫  π  -¹ ² ³ °

You are not logged in.

## #1 Maths Teaching Resources » Topology Video Lectures » 2010-10-29 23:02:12

Sekky
Replies: 1

Hello, I am currently creating an ongoing series of Topology video lectures and looking for students of an appropriate level for some accurate feedback. They are much in the style of the popular Khan Academy.

Link

Thank you for your time.

Yay he's banned

## #3 Re: Help Me ! » Reversing the Order of Integration » 2007-10-27 20:06:39

Maybe my question isn't clear.

How do you reverse this integral?

## #4 Re: Help Me ! » Reversing the Order of Integration » 2007-10-27 19:59:31

That in no way answered my question

## #5 Help Me ! » Reversing the Order of Integration » 2007-10-27 10:50:15

Sekky
Replies: 5

I've asked several people to explain this to me and each time they draw me some stupid little picture of a specific example and call it a proof and expect me to generalise it, so can somebody please explain to me algebraically how to generalise reversing the order of integrals.

## #6 Re: This is Cool » Flashmatics for AS3.0 » 2007-06-07 21:36:05

Ricky wrote:

My question is why flash?  I could see this being used for computationally heavy things (counting number of groups with some property for example), but flash fails in speed comparison to C or C++.

Plus, I know C/C++ in and out so I could probably be of more use with using such languages.  I took a look over code and flash syntax just looks ugly.  I try to take a more in depth look later.

Yes, I fully agree, Flash is computationally limited, but the purpose of this is not for speed maths, it's to provide more math capability in a language that I feel deserves it. I love Flash gaming, but the most advanced native math functions it has are trigonometric. AS3.0 doesn't even have a native vector class, so that's why I'm building it. Simply for the functions to exist and be available, not for ridiculously specialist mathematics.

Also, I don't agree with your statement about flash syntax being ugly, are you sure you're looking at the latest version? The original actionscript wasn't object oriented at all, AS2.0 was partially, but it still has some major annoyances. AS3.0 imho is beautiful, you may still be looking at AS2.0 since most people haven't made the leap yet and there's few resources around for it.

## #7 Re: This is Cool » Flashmatics for AS3.0 » 2007-06-07 06:03:37

Thanks delt, I'll edit my link

## #8 Re: Dark Discussions at Cafe Infinity » Mathsisfun: website publishing » 2007-06-07 02:46:24

I recommend http://www.streamline.net/, the Home user package. That's what I'm using atm, the customer service isn't great but the server has never failed on me so far.

## #9 This is Cool » Flashmatics for AS3.0 » 2007-06-07 02:38:51

Sekky
Replies: 7

I wasn't sure if this should be posted here, but it is maths, and it is cool, and I'm dying to plug it, so here it is.

http://stylebucket.co.uk/index.php?sect … lashmatics

This is a fairly ambitious project I've started called Flashmatics, which will hopefully someday be a decent build of compatible classes for more complex mathematics in AS3.0 for Flash CS3 and Flex. Basically, I lose interest in building games when I'm redoing the same old linear algebra math and particle dynamics so I figured "Why can't this be quicker?". I mean I'm basically doing the same thing over and over, so I'll try and generalise it all a little and get that little bit closer to the golden function MakeGameForMePlz();

Currently it only contains some abstract algebra concepts, primarily Group and Magma theory with some useful Set theory functions to enrich it. Linear Algebra is probably next on the cards to segway into particle dynamics.

So, I'm looking for feedback and constructive criticism on everything you see in that current zip from proficient mathies, semi-mathies and non-mathies. The code, the functionality, even the writing style in the manual and acessibility of the whole concept. and also suggestions for future, like if I were to add anything in the world in the next thirty seconds, what would it be.

Thanks in advance, Dan

## #10 Re: This is Cool » FLT DEMONSTRATION By Anthony.R.Brown » 2007-06-06 02:54:01

Anthony.R.Brown wrote:

(1) Prove it?

Prove Pi is a constant? Definition

Anthony.R.Brown wrote:

(2) So Recurrance does imply finite?

No, you're not listening, I didn't say that. I said non-recurrance does not imply finite (rational). For example, Pi is non-recurring, yet it is irrational, therefore the implication is false.

## #11 Re: This is Cool » FLT DEMONSTRATION By Anthony.R.Brown » 2007-06-04 02:04:57

Anthony.R.Brown wrote:

To luca-deltodesco

Quote:" (1) pi is not a random number, (2) it is not a recurring number, (3) it is not infinite "

A.R.B

(1) Show us a Pattern?

There is no discernable pattern to Pi, but it isn't random, it's constant.

Anthony.R.Brown wrote:

(2) Show us how it Ends?

Non-recurrance does not imply finite.

## #12 Re: This is Cool » 0.9999....(recurring) = 1? » 2007-06-04 02:02:37

Anthony.R.Brown wrote:

The above Proves TV can never Equal 1

No, it doesn't

## #13 Re: This is Cool » FLT DEMONSTRATION By Anthony.R.Brown » 2007-06-01 01:34:12

Anthony.R.Brown wrote:

For the Sequence 1,2,3,4,5,6,7,8,9.......etc. It's Impossible for Induction to Prove if the Number Sequence will End as an Odd Number or an Even Number!.....................................................

because it's not induced

And yes, I agree with Maelwys, and I can prove it by induction.

Let M(Maelwys) |-> True

P(n) : (M(Maelwys) = True) implies (Anthony gets argumentative and hormonal)

P(1) is the current thread, hence P(1) is true.

Anthony gets argumentative and hormonal is a universal constant, hence P(n) is invariant under n.

Therefore P(n) implies P(n+1).

Q.E.D

## #14 Re: This is Cool » FLT DEMONSTRATION By Anthony.R.Brown » 2007-05-31 08:16:42

Anthony, define your proposition, P(n), of the example you seem to be using.

Oh, by the way, failure to do so will just invalidate your claim, so drop the ad-hominem and just do it.

## #15 Re: This is Cool » FLT DEMONSTRATION By Anthony.R.Brown » 2007-05-30 03:05:26

Ok, Anthony, let's do it your way, by formal mathematical induction.

Define your proposition P(n), for your case.

## #16 Re: This is Cool » FLT DEMONSTRATION By Anthony.R.Brown » 2007-05-30 02:59:52

Anthony.R.Brown wrote:

To Maelwys

Quote:" Okay, what's the 1 case in 1000 that you can't prove with this? "

A.R.B

you have a shorty memory! 1,2,3,4,5,6,7,8,9..Odd or Even?

is WHAT odd or even?

## #17 Re: This is Cool » FLT DEMONSTRATION By Anthony.R.Brown » 2007-05-30 02:51:37

George,Y wrote:

Very clear logic, and I don't get why so many people are objecting him.

because that's copied and pasted, but more importantly it's arguing against him.

## #18 Re: This is Cool » FLT DEMONSTRATION By Anthony.R.Brown » 2007-05-30 02:48:44

Anthony, why can't you just admit that you don't understand concepts that are above your mathemtical capability? You're just trolling, stop it.

## #19 Re: Dark Discussions at Cafe Infinity » The Nine Planets » 2007-05-30 01:16:32

mathsyperson wrote:

 A planet has swept all other bodies out of its orbit, either by disrupting their path or colliding with them.

The third point is the one they added, which allowed them to say that Pluto wasn't a planet because its orbit overlaps with Neptune's. But surely if that's the case, then Neptune shouldn't be a planet either?

It's very possible that I'm misremembering something here, so please do correct me if you know better.

No, the difference is that they have different orbits. Pluto is one of thousands of objects in its orbit, and it's smaller than a lot of them.

## #20 Re: Dark Discussions at Cafe Infinity » The Nine Planets » 2007-05-29 20:16:41

There was a similar problem with Neptune's orbit when pluto was predicted, except when they found pluto it turned out after extensive observation that it wasn't in fact the "planet" affecting neptune in the way they had predicted, but pluto was classified a planet far too soon. As it happens, pluto is just one of many small objects in its belt.

## #21 Re: This is Cool » 0.9999....(recurring) = 1? » 2007-05-29 18:04:02

Anthony.R.Brown wrote:

So far no one on this site who thinks  Infinite/Recurring 0.9 = 1 has ever shown the Math! or as you have asked about the Calculations!!...........

We've shown countless proofs, you choose to ignore every single one, because you're bigotted.

## #22 Re: Dark Discussions at Cafe Infinity » What shape is the universe? » 2007-05-27 12:05:17

Dark matter is just a placeholder theory. Orbital behaviour implies that the universe is denser than we observe it to be, therefore dark matter. It's a horrid concept: "Not enough mass implies  undetectable/invisible mass." Great.

## #23 Re: This is Cool » FLT DEMONSTRATION By Anthony.R.Brown » 2007-05-27 08:13:41

Anthony.R.Brown wrote:

you must now be agreeing with what i'm saying! the Number Sequence is either Odd or Even depending on how far we Calculate!..............the problem cant be Reduced by Induction!

You never attempted to induce it, furthermore, it's non-sensical.

## #24 Re: This is Cool » 0.9999....(recurring) = 1? » 2007-05-27 08:11:46

Anthony.R.Brown wrote:

Infinite 1.111... x 0.9 will always have the .1 missing..............

Whatever this means, it isn't true.

## #25 Re: This is Cool » 0.9999....(recurring) = 1? » 2007-05-26 05:59:35

luca-deltodesco wrote:

but thats not counting, your'e going up and down the number scale.

That's counting, all you're doing is sequentially arranging the numbers. Essentially the fact that he's even suggested a sequence (which happens to be the accepted canonical sequence, although I can't see anyone doing it another way) implies that you can count them, because you can actively determine the next rational in sequence. You can't determine the next real in the same manner.

## Board footer

Powered by FluxBB