How to show completeness of C(K)?

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SUMMARY

To demonstrate that the space (C(K), d_infinity) is complete, where (K, d) is a compact metric space and d_infinity is the uniform metric, one must prove that every Cauchy sequence of continuous functions converges to a continuous function. This involves showing that for any Cauchy sequence {fn} in C(K), the pointwise evaluations {fn(x)} form a Cauchy sequence in the real numbers for each x in K. By leveraging the properties of compactness and the uniform metric, the proof can be constructed effectively.

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minibear
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The thing is: if you have (K, d) to be a compact metric space, then how to show (C(K) , d_infinity) is complete ?( d_infinity is uniform metric)

I know maybe I should use Cauchy or triangle inequality, but I am just not clear how to construct the proof.

Anyone who has any idea about that, please help. THX!
 
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To show that any metric space is complete, you must show that all Cauchy sequences converge, the definition of "complete".

Now, since C(k) is the set of continuous functions on K, with "sup" metric, each member of C corresponds to a continuous function and a Cauchy sequence on C(k) is a sequence of continuous functions on K, say {fn}. I would look at the sequence {fn(x)} for each x in K. Try to show that is a Cauchy sequence in K.
 

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