Is Infinity Divided by Infinity Equal to 1?

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Discussion Overview

The discussion centers around the question of whether infinity divided by infinity is equal to 1. Participants explore the implications of treating infinity as a number, the concept of indeterminate forms, and the role of limits in calculus.

Discussion Character

  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants suggest that infinity divided by infinity could resemble the case of 6 divided by 6 equaling 1, but express uncertainty about the nature of infinity.
  • Others argue that operations involving infinity are not defined in the same way as finite numbers, highlighting that limits must be examined instead.
  • One participant points out that the indeterminate form of infinity over infinity can yield various results depending on the specific limits involved.
  • Another participant emphasizes that infinity should not be treated as a constant number and that the quotient of two infinities can also be zero or infinity.
  • Some participants clarify that division by zero is not defined, and the indeterminate form of zero over zero can also yield different results based on limits.

Areas of Agreement / Disagreement

Participants generally do not reach a consensus, as multiple competing views remain regarding the treatment of infinity and the implications of indeterminate forms.

Contextual Notes

The discussion reveals limitations in understanding infinity and indeterminate forms, with participants noting the necessity of limits for proper evaluation. There are unresolved mathematical steps and definitions that influence the arguments presented.

Einstein's Cat
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Is infinity divided by infinity equal to 1? 6 divided by 6 is equal to 1 however as infinity resembles 0 in the sense that 0 dived by 0 is equal to 0, I am uncertain whether infinity divided by infinity would equal 1 or instead, infinity.
 
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Usually you can't do things like multiply or divide by infinity. It is not defined. Similarly, 0 divided by 0 is not 0. It is not defined.

What you can sometimes do is examine a limit. So ##\lim_{x->0} \frac{\sin(x)}{x}## is defined, and is 1. So in this sense, in this case, dividing a zero by a zero gives you 1. But only as the limit.

https://en.wikipedia.org/wiki/L'Hôpital's_rule
 
The uncertainties of the type ##\infty \cdot 0##, ##\infty/\infty## or ##0/0## acquire a definite value only as a limit, you can't simply operate with ##\infty## as being a number. So, unless we can go through the limit process it makes no sense to say that some uncertainty is equal to some value.
 
You are considering infinity as a constant number
Depends on the infinities you are working with quotient of two infinities can be zero or infinity too
 
Cheers for all your help
 
Einstein's Cat said:
Is infinity divided by infinity equal to 1? 6 divided by 6 is equal to 1 however as infinity resembles 0 in the sense that 0 dived by 0 is equal to 0, I am uncertain whether infinity divided by infinity would equal 1 or instead, infinity.
You have managed to pack a number of things that aren't true into a small number of words.

Is infinity divided by infinity equal to 1?
No.
The indeterminate form ##[\frac{\infty}{\infty}]## shows up in calculus as limits that can literally come out to any number, as well as negative or positive infinity. Here are some simple examples:
1. ##\lim_{x \to \infty}\frac{x^2}{x} = \infty##
2. ##\lim_{x \to \infty}\frac{x}{x^3} = 0##
3. ##\lim_{x \to \infty}\frac{x^2 + 3}{3x^2 - x + 7} = \frac 1 3##

as infinity resembles 0
No, not at all.

0 dived divided by 0 is equal to 0
No.
Division by 0 is not defined. The indeterminate form ##[\frac 0 0]## also shows up in calculus limits, and can come out to any number. Some examples of this:
1. ##\lim_{x \to 0}\frac{x^2}{x} = 0##
2. ##\lim_{x \to 0}\frac{x}{x^2}## does not exist
3. ##\lim_{x \to 0}\frac{x}{x^3} = \infty##
4. ##\lim_{x \to 0}\frac{\sin(2x)}{x} = 2##
 

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