Having some difficult with general concepts of metric spaces:(adsbygoogle = window.adsbygoogle || []).push({});

1) What is the difference between a subset and a subspace. let's say we have metric space X. and A is a set in that space. Is A necessarily a metric space itself?

2) Why is the metric of X ( d(x,y) for x,y belonging to X ) necessarily finite? Isn't the set of all real numbers a metric space, then how can you say that distance between any two numbers is finite?

Thanx!

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# Metric Spaces

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