Cube (algebra)
In arithmetic and algebra, the cube of a number n is its third power, that is, the result of multiplying three instances of n together. The cube of a number or any other mathematical expression is denoted by a superscript 3, for example 23 = 8 or (x + 1)3.
The cube is also the number multiplied by its square:
- n3 = n × n2 = n × n × n.
The cube function is the function x ↦ x3 (often denoted y = x3) that maps a number to its cube. It is an odd function, as
- (−n)3 = −(n3).
The volume of a geometric cube is the cube of its side length, giving rise to the name. The inverse operation that consists of finding a number whose cube is n is called extracting the cube root of n. It determines the side of the cube of a given volume. It is also n raised to the one-third power.
The graph of the cube function is known as the cubic parabola. Because the cube function is an odd function, this curve has a center of symmetry at the origin, but no axis of symmetry.