Octahedron in Cube: Proving the Possibility

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The discussion centers on the existence of an octahedron within a cube, with participants questioning the validity of the claim that it cannot exist. There is confusion about the definitions and visual representations being used, leading to a debate over the clarity of the initial question. Some participants express frustration at the contradictory statements regarding the octahedron's existence. The conversation highlights the need for precise definitions and clear communication in geometric discussions. Ultimately, the possibility of proving the octahedron's existence within a cube remains a point of contention.
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I heard somewhere that the Octahedron can't exist in the Cube exactly.

Is this true? Can't I prove that the octahedron in the cube?

Intuitively, they seems true. But I can't sure.
 
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Your question is not at all clear.
 
Octahedron_in_Cube.png
I meant this. I heard that this octahedron don't exist. But...
 
You are both drawing something and telling us it can't exist. Doesn't that bother you?
 
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