sqrt

(PHP 4, PHP 5, PHP 7, PHP 8)

sqrt — Square root

Description

sqrt(float $num): float

Returns the square root of num.

Parameters

num

The argument to process

Return Values

The square root of num 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

  • pow() - Exponential expression
  • M_SQRTPI - sqrt(pi)
  • M_2_SQRTPI - 2/sqrt(pi)
  • M_SQRT2 - sqrt(2)
  • M_SQRT3 - sqrt(3)
  • M_SQRT1_2 - 1/sqrt(2)