Evaluating Limits: Understanding the Definition and Common Misconceptions

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Homework Help Overview

The discussion revolves around evaluating limits, specifically the limit as x approaches 2 for a piecewise function defined as f(x) = 3 when x is an integer and f(x) = 1 otherwise. Participants express confusion regarding the application of the limit definition and its implications for the function's value at the point of interest.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants share their initial interpretations of the limit, with one expressing surprise at the result and questioning their understanding of the limit definition. Others prompt for a deeper exploration of what a limit signifies, particularly regarding the behavior of the function near the point rather than at the point itself.

Discussion Status

The discussion is ongoing, with participants actively questioning assumptions about the limit definition and its application to the given function. Some guidance has been offered regarding the distinction between the limit and the function's value at the point, but no consensus has been reached.

Contextual Notes

There appears to be a misunderstanding related to the definition of limits, particularly concerning the value of the function at the point of interest versus the behavior of the function as it approaches that point.

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Homework Statement


Evaluate the limits
lim x->2 f(x) if f(x) = 3, x an integer, or 1, otherwise.


Homework Equations





The Attempt at a Solution


I just 3 was the answer because I thought 2 is an integer and if x is an integer then the answer is 3. I was rather shocked to find that the answer is 1. I understand the definition of limits but I think I'm obviously mistaken about something. Thanks.
 
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appplejack said:

Homework Statement


Evaluate the limits
lim x->2 f(x) if f(x) = 3, x an integer, or 1, otherwise.

The Attempt at a Solution


I just 3 was the answer because I thought 2 is an integer and if x is an integer then the answer is 3. I was rather shocked to find that the answer is 1. I understand the definition of limits but I think I'm obviously mistaken about something. Thanks.
If you're shocked by that limit, then it's clear that you don't understand the definition of limits.
 
What is your intuitive understanding of what a limit is, appplejack?
 
lim x->c f(x)=L
as 'x' approaches c 'a number' from both sides (-,+) and F(x)= approaches L from both side (-,+).
 
Last edited:
appplejack said:
lim x->c f(x)=L
as 'x' approaches c 'a number' from both sides (-,+) and F(x)= approaches L from both side (-,+).

That's about right. But the definition of a limit doesn't say anything about the value of f(c) does it? It just talks about the value of f(x) where x is 'close to c'. Not equal to c.
 

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