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PHP sqrt() Function

PHP Math Reference Complete PHP Math Reference

Definition and Usage

The sqrt() function returns the square root of a number.

Syntax

sqrt(x)

Parameter Description
x Required. A number

Tips and Notes

Note: The sqrt() function will return -1.#IND if the parameter x is a negative number.

Example

In this example we will get the square root of different numbers:

<?php
echo(sqrt(0) . "<br />");
echo(sqrt(1) . "<br />");
echo(sqrt(9) . "<br />");
echo(sqrt(0.64) . "<br />");
echo(sqrt(-9))
?>

The output of the code above will be:

0
1
3
0.8
-1.#IND

PHP Math Reference Complete PHP Math Reference
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