• Hey Guest. Check out your NeoGAF Wrapped 2025 results here!

Math is hard

Status
Not open for further replies.
Red Scarlet said:
Isn't 1/3 an 'estimate' equal to .33333.... since it can't truly be proven, ie an approximation?
Take calculus for the love of god. You'll fail but at least you might have a chance of having a clue of what you're talking about.

Comments like this happen all the time in this board, but it usually pertains to gaming where it's more opinion then fact. Math is all about facts, about truth and non-truth, so you can't make comment like these without being completely, inarguably wrong.
 
Shompola said:
I see it as an infinite sequence of numbers converging to 1.

0.9, 0.99, 0.999, 0.9999, 0.99999 and so on

ah, yes, that infinite series does converge to one. You got a gold star! THANK YOU I LOVE YOU
 
Trident said:
ah, yes, that infinite series does converge to one. You got a gold star! THANK YOU I LOVE YOU
but how does it converge to 1 if you continually just add another 9? While you would never be able to fit another number between .999... and 1 at the same time you would also never fully reach one because you would still have an (literally) infinitely small missing piece.

If I gave you something that weighed on a scale to an infinite decimal place and the thing I gave you weighed .999... grams you would never be able to say I gave you something that weighed 1 gram without approximating.
 
I think a big problem here is that some people think that 1/3 and .333... are some naturally-evolving "numbers" that exist that mankind has harnessed for his own personal use.

In fact, they are just NOTATIONS of a number. 1/3 means nothing to nature -- it is just a notation that humans made up to signify something split into 3 equal pieces.

In the same way, we made up .333... as ANOTHER notation of the same number.

You don't have to prove that 1/3 = .333... because we made them up to be.

If we wanted to, we could have made up the notation GEORGEWASHINGTON<3 to also mean 1/3 and we would be having this argument with you asking me to prove that 1/3 = GEORGEWASHINGTON<3 .

But there's no proof because we made them up to be the same thing. They are just expressions of the same CONCEPT, and the concept is what's important here.
 
borghe said:
but how does it converge to 1 if you continually just add another 9? While you would never be able to fit another number between .999... and 1 at the same time you would also never fully reach one because you would still have an (literally) infinitely small missing piece.
Infinitely small = Zero.
 
LizardKing said:
ok, is .9999.... the same thing as writing: .9 and .99 and .999 and .9999 and .99999 and .999999 continuously forever?

It's something you can't visualize IMO since we don't really understand "forever". THis is really a debate between those thinking "but there will always be a small difference between 1 and .999...; no matter how close it gets to 1, it never quite gets there" and those who have a little calculus knowledge.

Here's the simplest way I can put it.

1.000...
- .999...
= .000...
 
LizardKing said:
ok, is .9999.... the same thing as writing: .9 and .99 and .999 and .9999 and .99999 and .999999 continuously forever?

I don't really know what that means.

it's the same as .9 + .09 + .009 + .0009 + .. forever
 
borghe said:
but how does it converge to 1 if you continually just add another 9? While you would never be able to fit another number between .999... and 1 at the same time you would also never fully reach one because you would still have an (literally) infinitely small missing piece.

If I gave you something that weighed on a scale to an infinite decimal place and the thing I gave you weighed .999... grams you would never be able to say I gave you something that weighed 1 gram without approximating.

dude, i can't derive all of the laws of mathematics. If you want to get a book, read the axioms upon which the system is based, and build it up from there, BE MY GUEST. But barring that, you can't really use intuition to override what's been discovered. You were saying you can't use finite arithmetic with infinite numbers, but the truth is you can't use finite THINKING with infinite numbers.

The way a continuous number line works IN MATHEMATICS is that every number has an infinite amount of numbers between them. There's no "infinitely small space," there's no space. There's only numbers. Either there is an infinite number of numbers between two of them, or they are the same number. There's no debate within mathematics.
 
well i took calculus and in that and throughout all my math classes (including calc physics) i was told that they are not the same number, at least when making calculations and whatnot. that does not mean there isn't a certain constraint, rule or theory in which to work in that makes them the same number however.
 
Man, I'm glad I never took Calculus, because it obviously make you insane. :)

Guys, an infinitely small difference is still a difference, i.e. not equal. Close enough to substitute one for the other, sure, but equal, no.
 
Squirrel Killer said:
Man, I'm glad I never took Calculus, because it obviously make you insane. :)

Guys, an infinitely small difference is still a difference, i.e. not equal. Close enough to substitute one for the other, sure, but equal, no.
You don't need Calculus; you just need logic. :)

There's no such thing as "an infinitely small difference." If you can't define it, it does not exist.
 
Squirrel Killer said:
Man, I'm glad I never took Calculus, because it obviously make you insane. :)

Guys, an infinitely small difference is still a difference, i.e. not equal. Close enough to substitute one for the other, sure, but equal, no.

Man, I'm glad I never took a chemistry class, because water and sodium don't explode on their own, so they obviously won't explode from just touching each other. Watch, I'll just throw this huge block of sodium into the tub with meOHMYGODITBURNS

INFINITY IS NOT AN INTUITIVE CONCEPT. YOU CAN'T JUST SIT BACK, WIDDLE WOOD, TALK ABOUT LIFE EXPERIENCES, AND EXPLAIN HOW IT WORKS
 
In the context of a number system,
in which "infinity" would mean something one can treat like a number.
In this context, infinity does not exist.


In the context of a topological space,
in which "infinity" would mean something that certain sequences of numbers converge to.
In this context, infinity does exist.


I think that is where the disagreement stems
 
Shompola said:
This is an interesting read for everyone here, including cocky Trident ;)

http://www.math.toronto.edu/mathnet/answers/infinity.html

That was an interesting read. I don't mean to give off the impression that I know everything there is to know about math. I certainly don't. I just get annoyed when people try to act as if math is some intuitive thing they can just think about for 10 minutes, relate to something they've seen, and explain away. If you've never taken calculus, and you want to talk about infinite series, then study first. You don't see me making comments about international economics just because I bought dinner once in Mexico.

Claiming mathematical laws are "bullshit" or derived by "throwing your hands up in the air" is some of the most disrespectful, ignorant, and aggrivating things somebody can do. Show some respect.
 
Trident said:
That was an interesting read. I don't mean to give off the impression that I know everything there is to know about math. I certainly don't. I just get annoyed when people try to act as if math is some intuitive thing they can just think about for 10 minutes, relate to something they've seen, and explain away. If you've never taken calculus, and you want to talk about infinite series, then study first. You don't see me making comments about international economics just because I bought dinner once in Mexico.

Claiming mathematical laws are "bullshit" or derived by "throwing your hands up in the air" is some of the most disrespectful, ignorant, and aggrivating things somebody can do. Show some respect.
but I think that article did a great job of showing support that it is a matter of perspective. .999... = 1 as long as you accept that infinity doesn't exist and eventually there will be convergence. which is ironic to the degree that you are using an infinitely repeating series of numbers but by default using the fact that infinity doesn't exist.
 
borghe said:
but I think that article did a great job of showing support that it is a matter of perspective. .999... = 1 as long as you accept that infinity doesn't exist and eventually there will be convergence. which is ironic to the degree that you are using an infinitely repeating series of numbers but by default using the fact that infinity doesn't exist.

This is where limits come in. Since I'm obviously not capable of explaining things well, here are some links:

http://en.wikipedia.org/wiki/Infinite#Infinity_in_real_analysis
http://en.wikipedia.org/wiki/Limit_of_a_sequence
http://en.wikipedia.org/wiki/Series_(mathematics)

If you can read and understand them, and still think that there is some uncertainty of perpsective involved, then I don't know what to say.

[Edit]
Ah-ha! Here's a great example. It can't be understood without a grasp of calculus, but those links above should help. This is an adaption of: http://en.wikipedia.org/wiki/Geometric_series#Infinite_geometric_series

take the infinite series 9 * 1/10^n for n = 0 to lim as n approaches infinity

this is the same as 9/10 + 9/100 + 9/1000 + ...
this is the same as .9 + .09 + .009 + .0009 + ...
this is the same as .999...

this is the same as 9/10 * the geometic series where x = 1/10 (see above link)
the geometric series is equal to 1/(1-x)

therefore, .999... is equal to 9/10 * 1/(1- 1/10) = 9/10 * 1/(9/10) = 9/10 * 10/9 = 1 !!!!!
 
Trident said:
This is where limits come in. Since I'm obviously not capable of explaining things well, here are some links:

http://en.wikipedia.org/wiki/Infinite#Infinity_in_real_analysis
http://en.wikipedia.org/wiki/Limit_of_a_sequence
http://en.wikipedia.org/wiki/Series_(mathematics)

If you can read and understand them, and still think that there is some uncertainty of perpsective involved, then I don't know what to say.
Add this one: http://en.wikipedia.org/wiki/Zeno's_paradoxes
 
Whatever, LakeEarth. I never claimed to be a math genius, that's how I heard it (that it is an accepted approximation), and well, sorry to piss you off so much. There are still many theories though, it isn't all black and white for math (I think). But hey, who cares, I'm a dumbshit and you're a bad motherfucker. Go you, you awesome genius, you. I'd definitely fail calculus though, and I really don't care. :lol

It's all semantic (and here's the keyword) bullshit. It's all trickery to make someone accept one 'proof' and then they have to accept the other. As numbers, I don't find them the same. You do. You have your logic, I have mine, the world moves on. This topic always brings out the snooty assholes. :) It's like an abortion debate for math nerds.

Math sucks.

LakeEarth said:

Possibly Nietzsche.
 
Mihail said:
You don't need Calculus; you just need logic. :)

There's no such thing as "an infinitely small difference." If you can't define it, it does not exist.
It is defined, actually. It's a surreal number named "iota". ;)
 
Hitokage said:
It is defined, actually. It's a surreal number named "iota". ;)

Man, you inspired me to try learning about surreal numbers. This stuff may be way over my head. Denying the law of the excluded middle? A Not Not = B doesn't mean A = B? Cry.
 
x = 0.999....
10x = 9.999...
10x - x = 9.999... - 0.999
9x = 9
x = 1

Is proof that 0.999... = 1 only if you assume that it also = 0.999... as a completely seperate number....... Otherwise the equation wouldn't work.........

x = 0.999....
10x = 9.999...
10x - x = 9.999... - 0.999
9x = 8.999...


You see.......... If 0.999... = 1 then doesn't it make sense to subtract 1 from 9.999... instead of .999... itself? With that you are pretty much admitting that this theory doesn't work out without the other. :-/ (oh btw I know this one isn't going to go down to well with those who have complete faith in math and all it's greatness ^^; )

What it all comes down to is the fact that math is man made...... Made made stuff is flawed...... It's called human error........ It's the same as trying to explain time....... When did it start? It must have started somewhere, but, where? There is no way to define this.......... It's also the same as trying to explain where the universe came from or where it ends....... If there is an end what's outside of it? These limits that humans create are the same as the limits used in math...... They can't possibly exist otherwise there would be nothingness.......... The concept of something that is infinate but with limits makes no sense it completely destroys the idea......... Basically 0.999... is just that......... 0.999... 1 is also 1........ But as math is a man made thing it must follow man made rules which state that 0.999... = 1 as without this math as a whole isn't complete........ It would mean there is no such thing as 1/3 in a decimal form.....


Hmmm so yeah, math is flawed, science is flawed and yeah religion is flawed as well...... Pretty much everything man made is flawed.............. I guess we can all be happy that language isn't....... :-/ Or is it...... *shrugs*
 
The 10x - x "common sense proof" is hardly a formal proof to use in a criticism of mathematics.

If you are going to examine 0.999... properly, I'd imagine(as I'm no expert on this) it's going to be through something like comparing 1 to limit of a series which approaches 1 as precision approaches infinite. In the end, it could be said that since the only difference between 1 and 0.999... is a surreal number, in real number terms they are equal.
 
Set theory :(

B = {X : X is an element of N and x < 5 and x^2 > 30}

Er, I missed the lecture. :lol

Any help?

Edit - Oh I'm guessing it's an empty set. Bastards.
 
Hey guys, please separate the n for me in this equation :
1-(n-1)/(n+2)>0,1
Pleaaaase, I've been thinking and thinking for some half hours yet, but all I get is BS
 
hmm i haven't done any math in 6 years, but it's quite easy:
1 is (n+2)/(n+2), you should be able to find you answer after that (n<28)
 
Use simple induction to show that n < n squared for all positive integers n greater than or equal to 2. State clearly your basis, induction hypothesis, and what you need to show given the induction hypothesis.
 
LOOK A NUMBER THEORY JOKE

every odd is prime, a series of proofs:

the mathematician's proof:

3 is prime, 5 is prime, 7 is prime, so by induction it must be true!

the physicist's proof:

3 is prime, 5 is prime, 7 is prime, 9 is experimental error, 11 is prime, 13 is prime... we can't find any experimental counterexamples so i guess it's true!

the engineer's proof:

3 is prime, 5 is prime, 7 is prime, 9 is prime, 11 is prime, 13 is prime, 15 is prime...

MY OWN APPENDIX

the computer scientist's proof:

primes are indivisible so by definition it's true!
 
Math rules.


Some math stuff...

1. Half of 13 is 7 (I can prove it. :) )


2.
batman68ks.jpg
 
Great King Bowser said:
Use simple induction to show that n < n squared for all positive integers n greater than or equal to 2. State clearly your basis, induction hypothesis, and what you need to show given the induction hypothesis.

1) base case, n < n^2
n = 2
2 < 2^2
2 < 4
TRUE for n = 2

2) lets assume it is true for n = p, this is our induction hypothesis
lets prove for n = p+1, induction step

p < p^2 wich can be rewritten as
p + 1 < p^2 + 1

if we can show that p^2 + 1 < (p+1)^2, then we also show p + 1 < p^2 + 1 < (p+1)^2

p^2 + 1 < (p+1)^2 =>
p^2 + 1 < p^2 + 2p + 1 =>
0 < 2p

TRUE for n = p+1
 
dude .999.... means an infinite number of 9s. You can't put a 1 at the end of it, because it's a NEVER ENDING SERIES of 9's.
 
Status
Not open for further replies.
Top Bottom