Find an f that satisfies these statements - Deltas and Epsilons

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SUMMARY

The discussion centers on finding a function f that satisfies the limit condition \lim_{x\rightarrow a} f(x)≠L, specifically the statement ∀ε>0 ∃δ>0∃ x:0<|x-a|<δ AND |f(x)-L|<ε. Participants clarify that the challenge lies in understanding that there must exist at least one ε for which no corresponding δ can be found, indicating that the limit does not exist. An example provided is lim x->0 x, which does not equal 1, serving as a proof of this concept.

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Homework Statement



Find an f that satisfies this statement:
[tex] \lim_{x\rightarrow a} f(x)≠L[/tex]

[tex]∀ε>0 ∃δ>0∃ x:0<|x-a|<δ AND |f(x)-L|<ε[/tex]

Homework Equations

The Attempt at a Solution



I'd just like a small hint on how I would go about finding a function. How can there be a delta for every epsilon and the rest of the statement is fulfilled, but there is no limit? The notation's just a tad confusing.
 
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Numnum said:

Homework Statement



Find an f that satisfies this statement:
[tex] \lim_{x\rightarrow a} f(x)≠L[/tex]

[tex]∀ε>0 ∃δ>0∃ x:0<|x-a|<δ AND |f(x)-L|<ε[/tex]

Homework Equations




The Attempt at a Solution



I'd just like a small hint on how I would go about finding a function. How can there be a delta for every epsilon and the rest of the statement is fulfilled, but there is no limit? The notation's just a tad confusing.

You aren't quantifying this right. There just has to be one epsilon without any corresponding delta. lim x->0 x isn't equal to 1. Prove it.
 

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