(PHP 4, PHP 5, PHP 7, PHP 8)
sqrt — Square root
$num
Returns the square root of num.
num
The argument to process
The square root of num or the special value NAN for negative numbers.
NAN
Приклад #1 sqrt() example
<?php// Precision depends on your precision directiveecho sqrt(9); // 3echo sqrt(10); // 3.16227766 ...?>
M_SQRTPI
sqrt(pi)
M_2_SQRTPI
2/sqrt(pi)
M_SQRT2
sqrt(2)
M_SQRT3
sqrt(3)
M_SQRT1_2
1/sqrt(2)
