Need a complete list of functions and thier inverses

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    Complete Functions List
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Discussion Overview

The discussion revolves around the request for a complete list of functions and their inverses, exploring the feasibility of such a list and the nature of functions and operations in mathematics. Participants engage in clarifying definitions and the implications of infinity in the context of functions.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant expresses frustration at the lack of a complete list of functions and their inverses, providing a partial list as an example.
  • Another participant argues that there are an infinite number of functions, most of which do not have inverses, and suggests that only a short list of common functions is easily available.
  • A third participant points out that the number of functions from \(\mathbb{R}\) to \(\mathbb{R}\) is so vast that compiling a complete list is not feasible, as it forms a proper class rather than a set.
  • Some participants clarify that operations such as differentiation and integration are not functions but rather inverse operations, while others contend that they should be considered functions.
  • There is a suggestion for a list of "opposite operations," but it is noted that this too would be extensive.
  • One participant claims that there are only a finite number of bijective functions, prompting a challenge for evidence of this assertion.
  • A later reply dismisses the original poster as a troll, indicating a breakdown in the discussion's constructive nature.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the feasibility of compiling a complete list of functions and their inverses. There are competing views regarding the nature of functions versus operations and the existence of finite versus infinite functions.

Contextual Notes

Participants express differing opinions on the definitions of functions and operations, and the discussion reflects uncertainty about the completeness and nature of mathematical lists.

Jeff12341234
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I can't find this anywhere on google.

I'm looking for a complete list of functions and their inverses.
Here's a partial list as an example
*, /
+, -
e^x, ln(x)
sin(), sin^-1()
d/dx, ∫
etc..

Why isn't there a list of all of them? You would think that some mathematician would find joy in compiling one...
 
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Assuming...just assuming...that you aren't trolling.

There are an infinite amount of functions, and I'm going to take a gander and say that the vast majority of them do not have inverses.

There are, however, a relativity short list of 'common' functions, and I'm sure it is very easy to google a list of their inverses, though you've listed a number already.

I'll stress here that neither ##\frac{d}{dx}## nor ##\int## are functions, though they are inverse operations.
Nor are multiplication, division, addition or subtraction, they are all operations.
 
There are [itex]2^{2^{\aleph_0}}[/itex] functions from [itex]\mathbb{R}\rightarrow \mathbb{R}[/itex]

This means that the number of functions from [itex]\mathbb{R}[/itex] to [itex]\mathbb{R}[/itex] is not only infinite, but a number of degrees above the smallest possible infinity.

Thus, I fear that a complete list of functions would not be very feasible.

If you want a list of all possible function between all possible sets. Then I'm afraid that they don't even form a set. The number of functions form a proper class. This means that is quite larger than anything mathematics can handle. So a list would be rather impossible.
 
Vorde said:
I'll stress here that neither ##\frac{d}{dx}## nor ##\int## are functions, though they are inverse operations.
Nor are multiplication, division, addition or subtraction, they are all operations.

I would actually consider all those things as functions...
 
Vorde said:
Assuming...just assuming...that you aren't trolling.

I'll stress here that neither ##\frac{d}{dx}## nor ##\int## are functions, though they are inverse operations.
Nor are multiplication, division, addition or subtraction, they are all operations.
ok. then what I'm looking for is a complete list of opposite operations.
 
Jeff12341234 said:
ok. then what I'm looking for is a complete list of opposite operations.

Still too large (= infinity).
 
no it's not. There are a few dozen we learn in algebra, another dozen from trig, only 2 from calc (d/dx and ∫ ), diff eq may add more to the list but I didn't notice any. you see? Get real. The question is not that hard. A list of opposite functions would be handy to have when solving for a variable in a complex algebraic equation.
 
Jeff12341234 said:
no it's not. There are a few dozen we learn in algebra, another dozen from trig, only 2 from calc (d/dx and ∫ ), diff eq may add more to the list but I didn't notice any. you see? Get real. The question is not that hard

So, you are saying that there are only a finite number of bijective functions in existence? Do you have any proof/evidence for that?
 
Anyway, the OP is just a troll, so I'm locking this.
 

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