PHP expm1() Function

Return exp() - 1:

<?php
echo(expm1(0) . "<br>");
echo(expm1(1) . "<br>");
echo(expm1(10) . "<br>");
echo(expm1(4.8));
?>

Definition and Usage

The expm1() function returns exp(x) - 1.

expm1( x);

Parameter	Description
x	Required. Specifies the exponent

Return Value:	'e' raised to the power of x minus 1
Return Type:	Float
PHP Version:	4.1+
PHP Changelog:	PHP 5.3 - expm1() is now available on all platforms