(PHP 4, PHP 5, PHP 7)
sqrt — Square root
$arg
) : float
Returns the square root of arg.
argThe argument to process
The square root of arg
or the special value NAN for negative numbers.
Example #1 sqrt() example
<?php
// Precision depends on your precision directive
echo sqrt(9); // 3
echo sqrt(10); // 3.16227766 ...
?>