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Cube Roots

Cube Roots

To find a cube root of a number, find a number which, when three versions of itself are multiplied together, gives you the original number. Finding a cube root is the inverse (opposite) operation to cubing a number.

The symbol used to show a cube root is , which is a square root sign but with a small 3 preceding it.

`root(3)27 = 3`, as three multiplied by itself three times gives 27.

A cube root of a negative number gives a negative answer: `root(3)-8 = -2`, as -2 x -2 x -2 = -8.

Example 1

`root(3)1000`

10 x 10 x 10 = 1000

Answer: 10

Example 2

Calculate `root(3)0.008`

0.2 x 0.2 x 0.2 = 0.008

Answer: 0.2