MHB Proving Uni.Conv. of Fn to F on (0,1): Questions & Answers

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A uniform continuous function sequence fn on the interval (0,1) converging uniformly to a function f implies that f is also uniformly continuous on (0,1). The user seeks to prove this by showing that the continuous extension Fn on [0,1] converges uniformly to F. They inquire about the validity of their approach and request guidance on proving the uniform convergence of Fn to F on [0,1]. A suggested method involves using the standard ε/3 argument and the Triangle Inequality to establish the proof. Overall, the discussion centers around proving the relationship between uniform continuity and uniform convergence in this context.
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Hello, today I have a question.

If uni.cont. function sequence fn on (0,1) is uni.conv. to f on (0,1), then f is uni.cont. on (0,1).

The above is true.
The wonder I have is...May I prove the above by this way?

This way: fn is uniform continuous on (0,1). So Fn is continuous on [0,1] (by continuous extention theorem.)
If I can prove Fn is uni. convergent to F on [0,1], (since Fn is cont. on [0,1]) F is cont. on [0,1] and f is uni. cont. on (0,1).

is this way true?
IF it is true, how can I prove Fn is uni.conv. to F on [0,1]?
IF not, could you show me some counter example?Please...(Sadface)(Sadface)(Sadface)
 
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I think you can use a standard $\varepsilon/3$ argument to prove this. Write out what uniform continuity and uniform convergence mean, using $\epsilon/3$ as the RHS. Then use the Triangle Inequality to finish.
 

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