Limit doesn't make sense according to the graph?

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Discussion Overview

The discussion revolves around the limits of the absolute value function as \( x \) approaches 0 from the positive and negative sides. Participants are examining the apparent contradiction between the calculated limits and the graphical representation of the function.

Discussion Character

  • Debate/contested, Conceptual clarification, Mathematical reasoning

Main Points Raised

  • One participant claims that the limits as \( x \) approaches 0 from the positive and negative sides yield contradictory results, suggesting \( \lim_{x \to 0^+} |x| = 1 \) and \( \lim_{x \to 0^-} |x| = -1 \).
  • Another participant challenges this claim, asking for clarification on the reasoning behind it.
  • A third participant questions whether the limits are indeed incorrect and mentions that their textbook contains a proof regarding this topic.
  • Several participants suggest that the original claim may be confused with the derivative of the absolute value function, indicating a potential misunderstanding of the limits involved.

Areas of Agreement / Disagreement

Participants do not reach a consensus, as there are conflicting views on the correctness of the limits and potential confusion with derivatives. The discussion remains unresolved.

Contextual Notes

There is a lack of clarity regarding the assumptions made about the limits and the definitions being used, particularly in relation to the derivative of the absolute value function.

tahayassen
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From first principles,

[tex]\underset { x\rightarrow { 0 }^{ + } }{ lim } |x|=1\\ \underset { x\rightarrow { 0 }^{ - } }{ lim } |x|=-1[/tex]

But if you look at the graph of |x|, it appears that both limits are approaching 0.

O_O
 
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Incorrect. Why do you think so?
 
arildno said:
Incorrect. Why do you think so?

Are the limits incorrect? My textbook has the proof.

I'll post it as soon as possible.
 
Are you sure you are notr talking about the DERIVATIVE of the absolute value function??
 
arildno said:
Are you sure you are notr talking about the DERIVATIVE of the absolute value function??

Makes so much sense! Thanks.
 

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