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Table 9.6 Math Object Methods (continued)
Method
Functionality
Math.tan(Number)
Math.toString(Number)
Converts Number to string
* Returns the value of E x where E is Euler's constant and x is the argument passed to it. Euler's constant is
approximately 2.7183.
Square Root, Power of, and Pi. The Math object comes with a number of common
mathematical constants (all uppercase), such as PI and natural log values, as well as meth-
ods to find the square root of a number, the power of a number, and so on. Example 9.20
demonstrates how to use some of these properties; the output is shown in Figure 9.24.
EXAMPLE 9.20
<html>
<body>
<h2>Math object Methods--sqrt(),pow()<br />
Math object Property--PI
</h2>
<h3>
<script type="text/javascript">
1
var num=16;
document.write("The square root of " +num+ " is ");
document.write( Math.sqrt(num) ,".<br />");
2
document.write("PI is ");
3
document.write( Math.PI );
document.write(".<br />"+num+" raised to the 3rd power is " );
4
document.write( Math.pow(num,3) + ".");
</script>
</h3>
</body>
</html>
EXPLANATION
1
The number 16 will be manipulated by Math methods and constants.
2
The Math object's sqrt() method returns the square root of number 16, which is 4.
3
The Math object's PI constant produces the value of PI.
4
The Math object's pow() methods raises and returns number 16 to the 3rd power,
which is 4096 (see Figure 9.24).

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