Epsilon-delta proof of sqrt of abs value of x

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SUMMARY

The limit as x approaches 0 of the function \(\sqrt{|x|}\) is proven to equal 0 using the epsilon-delta definition of limits. The proof establishes that if \(|x| < \delta\), then \(\sqrt{|x|} < \epsilon\) can be satisfied by choosing \(\delta = \epsilon^2\). This approach effectively demonstrates that for any positive epsilon, a corresponding delta can be found, ensuring the limit holds true. The discussion clarifies that negative epsilon values can be disregarded in this context since they do not affect the inequality.

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Prove that the limit as x->0 of [itex]\sqrt{\left|x\right|}[/itex] = 0

attempt:

[itex]\sqrt{\left|x\right|}[/itex] < [itex]\epsilon[/itex] when |x|<[itex]\delta[/itex]

-[itex]\epsilon[/itex] < [itex]\sqrt{\left|x\right|}[/itex] < [itex]\epsilon[/itex]

[itex]\left|x\right|[/itex] < [itex]\epsilon[/itex][itex]^{2}[/itex]

[itex]\delta[/itex]=[itex]\epsilon[/itex][itex]^{2}[/itex]

This seems to work...but I just ignored the negative epsilon since I can't square it in my inequality...I don't know if you are allowed to just ignore this?
 
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[tex] \sqrt{|x|} < \epsilon \Leftrightarrow |x| < \epsilon^{2}[/tex]

If you choose a [itex]\delta[/itex] such that:
[tex] 0 < \delta < \epsilon^2[/tex]
you are done.
 

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