Math Functions
PHP Manual

sqrt

(PHP 4, PHP 5, PHP 7)

sqrtSquare root

Description

float sqrt ( float $arg )

Returns the square root of arg.

Parameters

arg

The argument to process

Return Values

The square root of arg or the special value NAN for negative numbers.

Examples

Example #1 sqrt() example

<?php
// Precision depends on your precision directive
echo sqrt(9); // 3
echo sqrt(10); // 3.16227766 ...
?>

See Also


Math Functions
PHP Manual