Math 2.0

problem

Doubling the cube

Problem

Given the edge of a cube, construct with straightedge and compass alone the edge of a cube with twice the volume.

Remarks

For an edge of length 11, the new edge has length 23\sqrt[3]{2}. So the problem asks whether 23\sqrt[3]{2} is a constructible number. The answer is no: doubling the cube is impossible. The problem has solutions with other tools, such as a marked ruler or conic sections.

History

The problem is also called the Delian problem, after a legend about an oracle on the island of Delos. Hippocrates of Chios showed that it is equivalent to finding two mean proportionals between a segment and a segment twice as long. Pierre Wantzel proved in 1837 that no straightedge and compass solution exists.

Explanations

L1 human

The problem asks to build a cube with twice the volume of a given cube, using only an unmarked ruler and a compass. It is one of the three classical construction problems of Greek geometry.

What this node needs for W2
  • edge bounds both (0 of 1)

The writing levels say how complete the text of a node is. They do not measure its truth.

What depends on this

1 node uses this node, directly or through other nodes.

Sources

  1. Web https://en.wikipedia.org/wiki/Doubling_the_cube, lead section
  2. Web https://en.wikipedia.org/wiki/Doubling_the_cube, History