A question about uniform continuity (analysis)

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SUMMARY

The discussion centers on proving uniform continuity for the function f(x) = x^2 on a specified interval. The user proposes a proof using the inequality |f(x) - f(y)| = |x^2 - y^2| = |x - y||x + y|, establishing that |x + y| can be maximized at 6. By setting δ = ε/6, the proof demonstrates that |f(x) - f(y)| can be made less than ε, confirming uniform continuity. A minor correction is noted regarding the use of '<' instead of '<=' in the proof.

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Homework Statement



For question 19.2 in this link:

http://people.ischool.berkeley.edu/~johnsonb/Welcome_files/104/104hw7sum06.pdf

I came up with a different proof, but I'm not sure if it is correct...

Homework Equations





The Attempt at a Solution



Let |x-y|&lt; \delta

For |f(x)-f(y)| = |x^2 - x^y| = |x-y||x+y| &lt; \delta|x+y|, we know that the largest that |x+y| can be is 6. So if we let \delta= \epsilon/6...

We will have

|f(x)-f(y)| = |x^2 - x^y| = |x-y||x+y| &lt; \delta|x+y| &lt; (\epsilon/6)(6) = \epsilon

If this is true for the largest possibility, then it must be possible for all of them...

Do you think my answer is correct, or is there something that I'm missing?

Thanks in advance
 
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The last < should be a <=, but apart from that it is fine.
 

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