Javascript Reference - JavaScript sqrt() Method
The sqrt() method returns the square root of a number.
Browser Support
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|---|---|---|---|---|---|
sqrt() |
Yes | Yes | Yes | Yes | Yes |
Syntax
Math.sqrt(x);
Parameter Values
| Parameter | Description |
|---|---|
| x | Required. A number |
Return Value
the square root of a number.
If x is a negative number, NaN is returned.
Example
The following code shows how to calculate the square root of a number.
<!--from ww w. j av a2 s .c o m-->
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
function doMath() {
var inputNum1 = document.form1.input1.value;
var result = Math.sqrt(inputNum1);
document.form1.answer.value = result;
}
</script>
</head>
<body>
<form name=form1>
Enter Number: <input type="text" name="input1" size=10> <input
type="button" value="Calculate" onClick='doMath()'> <br>
The square root is: <input type="text" name="answer" size=20>
</form>
</body>
</html>