Does x^n f(x) Converge Uniformly on [0,1] as n Approaches Infinity?

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The discussion centers on the uniform convergence of the function x^n f(x) on the interval [0,1] as n approaches infinity, given that f(x) is continuous and f(1)=0. It is established that for any ε>0, there exists an N such that for all n>N, |x^n f(x)|<ε for all x in [0,1]. The endpoints of the interval are confirmed to converge to zero, and the continuity of f(x) ensures uniform convergence on compact sets. The conversation also touches on the nuances of uniform continuity and the implications for the convergence proof.

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Suppose f(x) is continuous on [0,1], and that f(1)=0. Prove that x^n f(x) converges uniformly on [0,1] as n \rightarrow \infty

By continuity, if |x-1|&lt; \delta then |f(x)|&lt; \epsilon for x \in [x_0 ,1] for some x_0 \in [0,1].

And there is some N such that if n>N, then |x^n|&lt;\epsilon since x^n \rightarrow 0 for x \in [0,1].

The endpoints work since x^nf(x) is 0 there. So I have an N that works for \{ 0 \} \cup [x_0, 1].

I'm having trouble getting the rest of the interval. I thought about covering the set and using compactness, but was wondering if there was a better way.
 
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You get uniform continuity on compact sets, my friend.
 
ZioX said:
You get uniform continuity on compact sets, my friend.

I'm asking about uniform convergence.

ETA: But the function would be uniformly continuous, giving me delta that works for all x in the interval.

Thanks.
 
ex-xian said:
Suppose f(x) is continuous on [0,1], and that f(1)=0. Prove that x^n f(x) converges uniformly on [0,1] as n \rightarrow \infty

By continuity, if |x-1|&lt; \delta then |f(x)|&lt; \epsilon for x \in [x_0 ,1] for some x_0 \in [0,1].
What's the point of this?

"If |x-1|&lt; \delta then |f(x)|&lt; \epsilon"

means that for x \in (1-\delta ,1], |f(x)|&lt;\epsilon. Why add the part about "for x \in [x_0, 1] for some x_0 \in [0,1]."?
And there is some N such that if n>N, then |x^n|&lt;\epsilon since x^n \rightarrow 0 for x \in [0,1].
This isn't true for x=1.
The endpoints work since x^nf(x) is 0 there. So I have an N that works for \{ 0 \} \cup [x_0, 1].
What is the definition of uniform convergence?
 

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