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Original post by SecretDuck
Economists use n / infinity to be equal to zero when evaluating probability distributions :yep:


Ah. Good example!
I just considered a finite supply and practically infinite demand. Everyone would get practically nothing if shared equally :yep:
Original post by Occams Chainsaw
Ah. Good example!
I just considered a finite supply and practically infinite demand. Everyone would get practically nothing if shared equally :yep:


If infinity exists in a power for an integral, in Economics, we always equal that term as zero. :yep:
In general infinity in mathematics exists, if a function get a certain value by increasing value of x. Then the graph of the function approaches the y-axis (without to ever 'touch' the y-axis) by increasing value of x. So inifnity means that the value of x can be optinal small or large (it depends on the function itself). The smaller/larger the value of x the more precisely the limit value is. All kinds of values of x which can be used to describe the limit value of a function are definable, in contrast to a certain number which are divided by 0, as this certain number is not clear after division (to put it crudely).
(edited 10 years ago)
Original post by SecretDuck
If infinity exists in a power for an integral, in Economics, we always equal that term as zero. :yep:

Interesting.
Original post by keromedic
Interesting.


Yeah - in pure maths, you may not get away it though.
Just hypothecitally but if I divided 13 by infinity, the result must be infinity too, as there are endless numbers which come into question to divide 13 (except 0), right?
Original post by tazmaniac97
Why does 13 divided by 0 not equal infinity? I really don't understand why?:confused:
My Maths teacher who has a PhD. in Mathematics told us. So basically I told my friend in another class, and she said it doesn't. So we both decided to have a bet on here on which one of us is right.

EDIT: stop repping me guys! I wanna keep my ruby's!


If 13/0 is infinity, then, logically, 12/0 is also infinity. 13/0 = 12/0; then it would follow that when you multiply by 0, 13 = 12, which obviously isn't true and that logic would make most maths teachers rip out their eyeballs.

Your maths teacher probably told you it was infinity because it's simpler than the real answer, 'undefined.' To an extent, infinity makes sense, but not completely. The alternative would be to tell you it was zero, like my little brother's teacher told him, and that would make me want to rip out my eyeballs.
Original post by paradoxicalme
If 13/0 is infinity, then, logically, 12/0 is also infinity. 13/0 = 12/0; then it would follow that when you multiply by 0, 13 = 12.


Last time I looked multiplication by zero did not produce anything other than zero but in this crazy thread anything is possible.
Original post by Mr M
Last time I looked multiplication by zero did not produce anything other than zero but in this crazy thread anything is possible.


That was my point. The logic of that is obviously flawed.
Undefinable means that a function is not clear enough to describe a value in numbers, if a certain number is used in the function
(in the case of 13, its 0). In contrast to that infinity means that many numbers of a function are possible to describe a limit value of a function, if they are used in the function. This is an important difference!
Original post by tazmaniac97
Stop it guys! Stop arguing guys, just get over yourselves! You're all wrong, I asked my maths teacher again (the one with the pHD) and he laughed at all of you, and he said that I'm right and you're wrong :unimpressed:


There are 2 possibilities here

1 - you did actually communicate with your maths teacher and he replied out of hours to confirm that he believe that n0=\dfrac{n}{0} = \infty in which case it is distressing to realise that people can hold a doctorate in a mathematics and actually think that

2 - you are lying


I am hoping that it is the latter
Reply 111
Original post by TenOfThem
There are 2 possibilities here

1 - you did actually communicate with your maths teacher and he replied out of hours to confirm that he believe that n0=\dfrac{n}{0} = \infty in which case it is distressing to realise that people can hold a doctorate in a mathematics and actually think that

2 - you are lying


I am hoping that it is the latter


The third option is that she misunderstood - which is significantly more likely than the first option given her rather "lights on but no-one's home" postings on this thread.
Original post by Noble.
The third option is that she misunderstood - which is significantly more likely than the first option given her rather "lights on but no-one's home" postings on this thread.


My view - if she originally misunderstood then she is still lying about contacting and receiving confirmation that we are all incorrect
Reply 113
what does it equal then
Original post by lucas13
what does it equal then


It does not equal anything

It is undefined
Reply 115
Original post by TenOfThem
My view - if she originally misunderstood then she is still lying about contacting and receiving confirmation that we are all incorrect


True. It wouldn't surprise me if what happened is she originally misunderstood and is now lying in some attempt to make herself not look stupid.
I'm closing the thread on the grounds that it is a) stupid and b) becoming personal.