Real Analysis: Are lebesgue measures metrics?

binks01
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Homework Statement


Are Lebesgue measures considered metrics?

The Attempt at a Solution


I have an elementary understanding of metrics and am currently learning about Lebesgue Integration. A Lebesgue measure as a length in Euclidean space should be a metric, but what about areas and volumes? I'm thinking no because metrics are distances, which to me means length. Is there a way I can prove this? Are there necessary properties of each that agree or disagree?
 
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A "metric" is a way of measuring the size of a set, not just the "length" of an interval. We use "metrics" in 2 and 3 dimensions all the time!
 
No. Because, as you said, a metric measures the distance between two things. A 'measure' (in the Lebesgue measure sense) measures the size of one thing. How can one be the other? The number of 'things' is different.
 
Oh, I see your point. Thanks.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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