Is the Function Uniformly Convergent on (0,1]?

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Discussion Overview

The discussion centers on the uniform convergence of the function \( f_n(x) = \frac{nx}{nx+1} \) defined on the interval \( (0,1] \). Participants explore the pointwise convergence of the function and seek to determine whether it converges uniformly on the specified interval.

Discussion Character

  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant states that \( f_n(x) \) converges pointwise to 0 when \( x=0 \) and to 1 otherwise.
  • The same participant argues that the function does not converge uniformly on \( [0,1] \) by providing a specific example with \( x=1/n \) leading to a limit of 0.5, suggesting that the supremum of the difference does not approach 0.
  • The participant expresses uncertainty about whether the function converges uniformly on the interval \( (0,1] \) and seeks assistance in demonstrating that the limit of the supremum of \( |f_n(x)-1| \) equals 0.
  • Another participant points out issues with the LaTeX formatting in the original post.
  • Subsequent replies inquire about the reason for the LaTeX issues and suggest not using capital letters for TEX.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the uniform convergence of the function on \( (0,1] \). There are competing views regarding the uniform convergence, and the discussion remains unresolved.

Contextual Notes

There are limitations regarding the clarity of the mathematical expressions due to formatting issues, which may affect the understanding of the arguments presented.

hmmmmm
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I am given f_n(x)=\frac{nx}{nx+1} defined on [0,\infty) and I have that the function converges pointwise to 0 \ \mbox{if x=0 and} 1\ \mbox{otherwise}

Is the function uniform convergent on [0,1]?

No. If we take x=1/n then Limit_{n\rightarrow\infty}|\frac{1/n*n}{1+1/n*n}-1|=0.5

which implies that Limit_{n\rightarrow\infty} sup |f_n(x)-1| is not 0.

I am then asked if it converges uniformly on the interval (0,1] which I think it does but how do I show that Limit_{n\rightarrow\infty} sup |f_n(x)-1|=0?

thanks for any help
 
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Your latex is screwed up.
 
Yeah do you know why that is?

thanks for any help
 
hmmmmm said:
Yeah do you know why that is?

thanks for any help

don't put TEX in capitals.
 

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