# PHP asinh() Function

PHPServer Side ProgrammingProgramming

## Definition and Usage

The asinh() function calculates inverse of hyperbolic sine of given parameter. In other words, the return value of asinh() is hyperbolic sine of given parameter. A inverse hyperbolic sine function is defined as

asinh(x) = log(x+sqrt(pow(x,2)+1))

This function returns a float value.

asinh( float $arg ) : float ## Parameters Sr.NoParameter & Description 1arg A floating point value whose inverse hyperbolic sine is to be calculated ## Return Values PHP asinh() function returns inverse hyperbolic sine ratio of given parameter. ## PHP Version This function is available in PHP versions 4.x, PHP 5.x as well as PHP 7.x. ## Example Live Demo Following example calculates asinh(pi/2) which we can verify using the definition − <?php$arg=M_PI_2;
$val=asinh($arg);
$ret=log($arg+sqrt(pow($arg,2)+1)); echo "asinh(" .$arg . ") = " . $val . "\n"; echo "using formula = " .$ret;
?>

## Output

This will produce following result −

asinh(1.5707963267949) = 1.2334031175112
using formula = 1.2334031175112

## Example

Live Demo

Following example uses deg2rad() function to convert degrees to radians and then uses asinh(30) −

<?php
$arg=deg2rad(30);$val=asinh($arg); echo "asinh(" .$arg . ") = " . $val; ?> ## Output This will produce following result − asinh(0.5235987755983) = 0.50221898503461 ## Example Live Demo Let's check find out asinh(0). It returns 0 − <?php$arg=0;
$val=asinh($arg);
echo "asinh(" . $arg . ") = " .$val;
?>

## Output

This will produce following result −

asinh(0) = 0

## Example

Live Demo

Following example computes asinh(pi)

<?php
$arg=M_PI; // pi$val=asinh($arg); echo "asinh(" .$arg . ") = " . \$val;
?>

## Output

This will produce following result −

asinh(3.1415926535898) = 1.8622957433108