Uniform Convergence of sequence

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SUMMARY

The discussion centers on the uniform convergence of the sequence \( x^n \) for \( 0 < x < 1 \). It is established that the limit function \( f(x) = \lim_{n\rightarrow \infty} f_{n}(x) = 0 \). However, the sequence \( f_n(x) \) is not uniformly convergent, as it fails to satisfy the condition \( |f_n(x) - f(x)| < \epsilon \) for all \( n \geq N \) across the interval. Specifically, for any fixed \( N \), there exists an \( x \) close to 1 that invalidates the uniform convergence condition.

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siddharth
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Discuss the uniform convergence of the following sequence in the interval indicated

[tex]{x^n} , 0< x <1[/tex]

Now,
[tex]f(x) = \lim_{n\rightarrow \infty} f_{n}(x) = 0[/tex]
Therefore given any small [tex]\epsilon > 0[/tex], if there exists [tex]N[/tex] such that [tex]|f_n(x)-f(x)| < \epsilon[/tex] for all [tex]n \geq N[/tex] for all x in the given interval, then f_n(x) is uniformly convergent.

That gives

[tex]x^n < \epsilon[/tex]

[tex]n > \frac{\log \epsilon }{\log x}[/tex]

So, it is not possible to fix an [tex]N[/tex] such that the above condition is satisfied for all values of n>N because for a given value of N, I can always find a value of x close to 1 such that the above condition is not valid.
Hence [tex]x^n[/tex] is not uniformly convergent in the given interval.

Is my above reasoning correct?
 
Last edited:
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xn is convergent, just not uniformly convergent. Does that make sense?
 

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