Doubling the cube given length times . In music theory, a natural analogue of doubling is the octave (a musical interval caused by doubling the frequency of a tone), and a natural analogue of a cube is three repetitions of the same interval. In this sense, the problem of doubling the cube is solved by the major third in equal temperament. This is a musical interval that is exactly one third of an octave. It multiplies the frequency of a tone by , the side length of the Delian cube. Doubling the cube Doubling the cube, also known as the Delian problem, is
Square root of 5 of a side located on one the faces containing that vertex and opposite to it, are in the ratio This follows from the geometrical relationships between a cube and the quantities (edge-to-face-diagonal ratio, or distance between opposite edges), (edge-to-cube-diagonal ratio) and (the relationship just mentioned above). A rectangle with side proportions 1: is called a "root-five rectangle" and is part of the series of root rectangles, a subset of dynamic rectangles, which are based on and successively constructed using the diagonal of the previous root rectangle, starting from a square. A root-5 rectangle is particularly notable in that it can