Help with reversing a function

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Discussion Overview

The discussion revolves around the challenge of reversing a function, specifically isolating the variable x in terms of f(x). Participants explore the feasibility of finding an inverse function and the implications of the function's properties on this process.

Discussion Character

  • Exploratory, Debate/contested, Homework-related

Main Points Raised

  • One participant seeks guidance on how to isolate x from f(x) to solve for x.
  • Another participant expresses skepticism about the possibility of inverting the function.
  • A different participant questions the utility of inverting the function, suggesting it may not be one-to-one and therefore lacks an inverse. They propose methods to demonstrate this, such as finding two distinct values that yield the same output or using the horizontal line test on the function's graph.
  • One participant suggests considering numerical methods as an alternative to analytic solutions if the goal is simply to find a value for x.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the possibility of inverting the function. There are competing views regarding the function's properties and the methods to approach the problem.

Contextual Notes

Some limitations include the assumption that the function may not be one-to-one, which affects the existence of an inverse. The discussion also highlights the potential need for numerical methods without resolving the specifics of the function in question.

Trekky0623
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I need to know how to start this.

Basically, I'm trying to isolate x on one side, so that I can input f(x) and solve for x, instead of the other way around.

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don't think that is possible
 
Why would you ever want to invert such a useless function?

If it's homework and you're having trouble solving for x in terms of f(x), then there's a good chance the function is not one-to-one and thus has no inverse. The way you would prove this, though, is to find two values, x and y, such that f(x) = f(y). Alternatively, if you can plot the graph of the function, you can use a horizontal line test to see if it's one-to-one. If you can find a horizontal line that passes through two distinct points on the graph, then you can't invert it.
 
Alternatively, if you just want the answer for yourself, you should consider numerical methods instead of analytic solutions.
 

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