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## #1 Re: This is Cool » Question about Infinity » 2006-06-06 19:39:25

But you can't have 2∞ can you? 2∞ would just be infinity. If ∞ - ∞ = 0, then 2∞ - ∞ = 0 too as well as ∞² - √∞ = 0.

But I was also thinking about the universe. It was described to have begun as a single point infinitesimal (is that the word?). If this is so than it would be impossible for the universe to be of any real size at this stage unless its size was increased by infinity would make the size be ... bah now my brain hurts.

## #2 This is Cool » Question about Infinity » 2006-06-05 21:03:21

Zmurf
Replies: 12

Something my friend and I were pondering. Wouldn't the difference of infinity and infinity be infinity and not zero?

That is to say, ∞ - ∞ = ∞. I'm basing this on the understanding, however, that infinity is not a constant.

## #3 Re: This is Cool » The 6th of June, 2006 » 2006-06-05 20:48:29

I doubt God or Satan run by the Georgian calandar, and if they did, we have/had nothing to worry about anyway. The date is the 6/6/2006, 06 is short for 2006 but it's not the date. The guys back in the in the year 6AD on the other hand ...

## #4 Re: Help Me ! » Mechanics 1 - Kinematics Problem » 2006-06-05 19:38:48

I got 1.667 for the accelaration.

With a = (v - u)/t, would t be equal to 6 (the total time from A to C) or 2 (The difference in time between AB and BC) or something different. If it's 2 then i got 5 for the accelaration which seems really wrong.

## #5 This is Cool » The reason why x/0 = no solution. Simply put. » 2006-05-31 22:23:57

Zmurf
Replies: 14

People often ask in maths class over the years why any number devided by 0 is no solution. They often ask why it isn't equal to 0, infinity or an imaginary number. Well I have a very simple answer to this.

If you divide any number like so:

6/3 = 2

You can find which number the numerator was by multiplying the denominator by the answer.

So y/3 = 2, y = 6.

y can only possibly be 6. There is no other possible solution.

y/3 = 0, y = 0.

Once again there is only one possible solution.

But in the case of of the following.

3/0 = x

The product of x and 0 does not give the numerator, 3. It gives 0. This does not follow our rule. So in the algabraic expression:

x/0 = y. Supposing y was magically given, x could could equal an infinite number of things. x/0 in this case would have more than one possible answer and thus, the problem yields no solution.

## #6 Re: Help Me ! » How do you find X? » 2006-05-29 17:48:15

You can also express it as something like the following.

250 = x^x

x^x = 4^4 - 2^2 - 1^1 - 1^1.

Is there anway to take the collection of these numbers arrange them to accurately form x^x?

Heres my C++ app for finding an appraximation for x:

``````// System Includes.
#include <iostream>
#include <math.h>

// Other Includes.

// Namespaces.
using namespace std;

// Main Function.
int main(){
// Variables.
double n = 0.0;
double x = 0.0;
double step = 1.0;
double out = 0.0;

// Interface.
cout << "n = x^x" << endl;
cout << "n = ";
cin >> n;

// Calculations.
for (x = 1.0; x < 16.0; x += step){
if (pow(x, x) == n){
cout << "x = " << x << endl;
break;
}
else if (pow(x, x) > n){
if (step < 0.0001){
cout << "x = " << x << endl;
break;
}
x--;
step /= 10;
}
}

// Let user see display.
system("PAUSE");

// Return no value.
return 0;
}``````

## #7 Re: This is Cool » My 3D engine: reinventing the wheel » 2006-05-22 19:53:04

Oh great! I didn't know there were other programmers on the forum. This engine looks very impressive, my friend and I are working on just a simple program for drawing 3 dimensional objects. We got it to render properly and we were going to move on to texturing but it just got too complicated.

I suggest you use the OpenGL API in conjunction with C/C++. It will be incredibly faster and more accurate than gamemaker. Gamemaker works on pixel coordinates, that is to say, it draws a line from position x1,y1 -> x2,y2 on your monitor, making it extremely innacurate. OGL (and DirectX but I prefer OGL, it's much cleaner) works by generating the line in a pseudo 3d environment, then takes a digital image of this environment based on the camera position and pastes this image on your screen.

## #8 Re: Help Me ! » Bart Simpson Rocks » 2006-05-19 20:28:47

Bart Simpson has 1 season left. Maths will go on for ever.
Maths: 4, Bart Simpson: 0

## #9 Re: This is Cool » The Exact Value of PI. Well, not exactly ... » 2006-05-16 18:20:46

The x-axis becomes the value of n, and the y-axis becaomes the answer to the sum after the n'th iteration.

## #10 Re: Help Me ! » Conventions for Geometry Proofs » 2006-05-15 17:56:48

Oh thankyou this is very helpful!

## #11 Help Me ! » Conventions for Geometry Proofs » 2006-05-15 14:04:59

Zmurf
Replies: 2

I really need help with this. In my maths exams I can easily find the answers for the questions. But I'm losing valueble marks becausing I'm not writing the proofs correctly. I don't know how! And when it is explained in class I just don't get it, I don't know which proves to use where. I keep getting co-interior and alternate and stuff all mixed up. Can anyone help me with some good methods for proof in gemoetry. I just can't seem to express my logic mathematically.

## #12 Re: Help Me ! » Sum of an Infinite Series » 2006-05-14 18:48:40

Couldn't that be re-written as:

I havn't had much experience with lim, and can't remember what it signifys. What exactly is your question?

Edit: Upon refreshing my memories with limits (The almighty Wikipedia ) The formula I specified is incorrect. I don't know if you already know what your formula does or not. Could supply a bit more information? As far as I can tell, your forumla is getting as close to zero as possible and then bigger at a slower rate depending on the size of n.

If you were to make n = 900. It would make the sum of:

Where i was increasing from 1 until it reached 900.

lol

## #14 Re: Help Me ! » MidPoint of the line passing through the circle » 2006-05-12 12:37:38

Yes, I know that way, I wanna know why it won't work when I use perpundicular distance.

## #15 Re: Dark Discussions at Cafe Infinity » 2006 Commonwealth Games » 2006-05-11 22:32:33

On a quiz about commonwealth games there was a question.

What is another name ofr the Commonwealth Games.

A) Olympics Rip off
B) The Australian Games
C) The Friendly Games
D) The Less-Common-Wealth Game

22% Said B.
3% Said C (Which was the right answer)
2% Said D.

It's funny 'cause it's true.

## #16 Re: Dark Discussions at Cafe Infinity » imballanced brain... » 2006-05-11 22:28:46

I don;t think either side of my brain is more developed, actually, if I could drill a door into the side of my school, I could store stuff in the void between bone and brain.

## #17 Re: Guestbook » Fun??? » 2006-05-11 22:21:28

Sounds like he's trying to make fun of the forum.

## #18 Help Me ! » MidPoint of the line passing through the circle » 2006-05-11 18:53:41

Zmurf
Replies: 6

Ok we got this question in maths.

Find the midpoint M, of the line passing through points A and B of circle:

if the line has equation:

Noone could get it, well I could of but I didn't want to use the conventional method, I wanted to use a method noone else would think of because that the kinda of guy I am. Plus the teacher didn't give us enougth time before she excited and confidently told us how to do it.

The way she told us how to do it was with some simultaneous stuff, I wasn't listening I was working on my method.

I found that the midpoint of an interval under the circumstances above is the point in which the perpundicular line to the interval specifed passes through the center of the circle.

So by finding the perpundicular distance I found the hypotinuse of the triangle whos base and height will give the coordinates of M in relation to C if C is the center of the circle.

Now this is all works in theory. But I couldn't get it to work on my page. I knew one of the angles of the triangle because I knew the gradient of the line. Using atan(-1/m) of the line given. Using Sin Cos Tan (I refuse to use the childish word SOHCAHTOA) I can calculate the coordinates of M. But when I did so, I recieved irrational answer. But the answers my teacher found were very rational.

Heres my working out: (Or should i say not-working out, hahaha ... bad joke )

It's obviously very wrong. Can someone help me out?

## #19 Re: This is Cool » Yeah! » 2006-05-11 18:34:19

Well done!

Thats like the School Certificate in Australia, I got band 5 (87%) oh yea! And I'm coming first in the grade for extension 1 mathematics. Heh, and my teacher told me I should to general maths, TAKE THAT!

## #20 Jokes » Lawyers » 2006-05-10 20:46:53

Zmurf
Replies: 7

If your a lawyer, please don't take offence. Though, I don't understand why you would be on a forum dealing with reason. (That wasn't the joke)

What doe you call 500 dead lawyers at the bottom of the ocean?

## #21 Re: Jokes » English » 2006-05-10 20:44:25

Yea, I never understood why you would want to "take" a dump.

## #22 Re: Jokes » stupid stuff... » 2006-05-10 20:35:38

MathsIsFun wrote:

"If the Iranians were to have a nuclear weapon they could proliferate."

I don't see how this quote is at all in fault. If they were to get there hands on nuclear weapons, there ability to create nuclear weapons would be exponential. Ie; Proliferate.

## #23 Re: Jokes » Proofs: What to do when you're out of time » 2006-05-10 20:31:53

ryos wrote:

Proof by quantum mechanics: > <---Right there is a quantum singularity that should (cross your fingers) expand into the correct proof when observed by one who knows it.

Can't argue with H-Dog (Steven Hawking). lol.

Find the equation for the line whos table of values is displayed below:

EASY. y = xy / y

Can you believed I got that right in an exam? It made me very worried.

Lol. Alright.

## #25 Re: Puzzles and Games » Smiley Face » 2006-05-10 18:05:30

Where is the smiley face, exactly what should I be looking for?