Multiplying a number by itself, then multiplying by itself *again* gives the **cube** of a number:

4 x 4 x 4 = 4^{3} = 64.

The small 3 (the index) after the number indicates that it is being cubed.

A negative number that is cubed will result in a negative number:

-3^{3} = -3 x -3 x -3 = -27

A number less than 1 will result in a smaller number:

0.2^{3} = 0.2 x 0.2 x 0.2 = 0.008

Fractions can also be cubed:

(`frac(1)(2)`)^{3} = `frac(1)(2)` x `frac(1)(2)` x `frac(1)(2)` = `frac(1)(8)`

What is 0.5^{3}?

Work out 5 x 5 x 5 = 125: there were 3 x 1 decimal places in the original numbers, make sure that there are three decimal places in the answer = 0.125.

Answer: 0.125

Calculate (2 + 3)^{3}.

Calculate the brackets first: 2 + 3 = 5.

5^{3} = 5 x 5 x 5 = 125.

Answer: 125

See also Cube Sequences

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