Continuous functions on metric space, M

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If every continuous function on a metric space M is bounded, it implies that the image of any continuous mapping from a set X to M is contained within a bounded subset of M. A function f:X→M is considered bounded if there exists a point x in X and a radius ε such that the entire image f(X) fits within a ball of radius ε centered at f(x). The discussion highlights the need for context to fully understand the implications of boundedness in relation to continuous functions. Additionally, the continuity of the identity function f(p) = p indicates that M itself must also be bounded. Understanding these concepts is crucial for analyzing the properties of continuous functions within metric spaces.
roman93
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If every continuous function on M is bounded, what does this mean?

I am not sure what this function actually is... is it a mapping from M -> M or some other mapping? Is the image of the function in M? Any help would be greatly appreciated!
 
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roman93 said:
is it a mapping from M -> M or some other mapping?

I suggest that you explain where you saw this statement and quote it exactly.
 
A map f:X\rightarrow M where X is a set and M is a metric space, is called bounded if the image f(X) is bounded. This means that there is an x\in X and an \varepsilon>0 such that f(X)\subseteq B(f(x),\varepsilon).

This is what I would call bounded. But you will need to specify the context.
 
Since f(p)= p is continuous, one thing that tells you is that M itself is bounded!
 
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