The **Math **object has a number of intrinsic properties and methods. The properties are specific numbers.

# Using the Math Object

One of these specific numbers is the value of pi (approximately 3.14159...). This is the value of the **Math.PI** property, which is used in the following example.

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// A radius variable is declared and assigned a numeric value. var radius = 4; var area = Math.PI * radius * radius; // Note capitalization of Math and PI. |

One built-in method of the **Math** object is the exponentiation method, or **pow**, which raises a number to a specified power. The following example uses both pi and exponentiation.

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// This formula calculates the volume of a sphere with the given radius. var volume = (4/3)*(Math.PI*Math.pow(radius,3)); |

Another example is as follows:

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var x = Math.floor( Math.random()*10 ) + 1; |

The **Math** object cannot be explicitly constructed; it is always available to the program.