Proving the Equivalence of Solving Equations and Finding Functions

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Discussion Overview

The discussion revolves around the equivalence of solving equations and finding functions, specifically addressing the conditions under which a function can be substituted into an equation to yield an identity. The scope includes theoretical exploration and mathematical reasoning.

Discussion Character

  • Exploratory
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant proposes a proof that solving for a variable in an equation is equivalent to finding a function that, when substituted into the equation, reduces it to an identity.
  • Another participant suggests that the implicit function theorem may be relevant to the proof.
  • A different participant argues against the initial claim by providing a counterexample involving the equation x_1=x_1^2, indicating that the function f(x_2)=0 reduces to an identity but does not capture all solutions.
  • The original poster acknowledges a flaw in their wording and clarifies that the problem should account for multiple independent solutions, restating the equivalence in terms of finding a function that satisfies the identity condition.

Areas of Agreement / Disagreement

Participants express disagreement regarding the validity of the initial claim, with at least one counterexample presented. The discussion remains unresolved as participants have differing views on the equivalence and the implications of the proposed proof.

Contextual Notes

The discussion highlights limitations in the initial formulation of the problem, particularly regarding the treatment of multiple independent solutions and the conditions under which the equivalence holds.

tickle_monste
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I've got a proof but I'll wait a couple days to post mine to give you guys a chance to take a crack at it.

Prove that:

For all equations E(A1, ... , An), solving for Ai is equivalent to finding the function
f(A1..A(i-1),A(i+1)...An), such that when f is substituted in E in place of Ai, E reduces to an identity (i.e. 0 = 0, 1 = 1, a^2 + b^2 = c^2, etc.)

Use whatever axioms you'd like.
 
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Seems like implicit function theorem proof.
 
Not necessary.
 
I don't think this is true. If you consider the equation x_1=x_1^2 and the function f(x_2)=0 reduces to the identity 0 = 0, but misses the solution x_1=1.
 
My wording of the problem was poor, I forgot to account for multiple independent solutions. So, here it is, better worded:
Finding a solution of Q in the equation is equivalent to finding a function f, such that when f is substituted for Q in the equation, the equation will reduce to an identity.

Both of your solutions satisfy this property, no other number satisfies this property and no other number is a solution.
 

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