The cube of a number is the third power of . Similarly one may speak of the cube of an element in any semigroup with the operation denoted multiplicatively (cf. general
associativity).
The volume of a cube (i.e. regular hexahedron) with edge length is ; hence the name.
The cube function from
to
is injective, but not as a mapping from
to
; one has always when
, the primitive third root of unity.
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