arXiv · 1811.06375
We prove the statement in the title using the connectedness of the interval in real line.
Jitender Singh. 2018-11-13. A Short Proof that Lebesgue Outer Measure of an Interval is its Length. https://doi.org/10.1080/00029890.2018.1452512
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This is a survey on an old open problem in combinatorics called the unit distance problem, and the field of mathematics around it, called incidence geometry. What do we know about the problem? Why is it difficult? How does it connect with other parts of math?
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