Unit cube

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{{short description|Cube with ed u are a beach beaches are ugly |thumb|300px|right|Unit cube]] A unit cube, more formally a cube of side 1, is a cube whose sides are 1 unit long. [1] [2] The volume of a 3-dimensional unit cube is 1 cubic unit, and its total surface area is 6 square units. [3]

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Unit hypercube

The term unit cube or unit hypercube is also used for hypercubes, or "cubes" in n-dimensional spaces, for values of n other than 3 and edge length 1. [1] [2]

Sometimes the term "unit cube" refers in specific to the set [0, 1]n of all n-tuples of numbers in the interval [0, 1]. [1]

The length of the longest diagonal of a unit hypercube of n dimensions is , the square root of n and the (Euclidean) length of the vector (1,1,1,....1,1) in n-dimensional space. [2]

See also

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Hoffmans packing puzzle Assembly puzzle named after Dean Hoffman

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References

  1. 1 2 3 Ball, Keith (2010), "High-dimensional geometry and its probabilistic analogues", in Gowers, Timothy (ed.), The Princeton Companion to Mathematics , Princeton University Press, pp. 670–680, ISBN   9781400830398 . See in particular p. 671.
  2. 1 2 3 Gardner, Martin (2001), "Chapter 13: Hypercubes", The Colossal Book of Mathematics: Classic Puzzles, Paradoxes, and Problems : Number Theory, Algebra, Geometry, Probability, Topology, Game Theory, Infinity, and Other Topics of Recreational Mathematics, W. W. Norton & Company, pp. 162–174, ISBN   9780393020236 .
  3. Geometry: Reteaching Masters, Holt Rinehart & Winston, 2001, p. 74, ISBN   9780030543289 .