The **`expm1()` method** from the `java.lang.Math` class can be used to calculate the exponential function $e^{x}- 1$. It takes the value $x$ as argument and returns the result of  $e^{x}- 1$.

#   
## Syntax

---
```java
static double expm1(double x)
```
---

## Parameters
The `expm1()` method takes the following input parameter.

- **`x`**: A `double` type argument value that represents the power of $e$ in the expression $e^x - 1$.

## Return value
The method returns a primitive `double` type value which is the result of the $e^x - 1$ expression.

* The result is `NaN` if the argument value is NaN.
 
* The result is `-1.0` if the argument is negative infinity.

* The result is `positive infinity` if the argument value is positive infinity.

## Code

* Case 1: Positive number as an argument.

* Case 2: Negative number as an argument.

* Case 3: Zero as an argument value.

* Case 4: Positive infinity as an argument.

* Case 5: Negative infinity as an argument.


Execute the code below to see the output.

// Load library
import java.lang.Math;
// Main class
class EdPresso {
    public static void main( String args[] ) {
        System.out.println(Math.expm1(6));
    }
}

Case#1

// Load library
import java.lang.Math;
// Main class
class EdPresso {
    public static void main( String args[] ) {
        System.out.println(Math.expm1(-6));
    }
}

Case#2

// Load library
import java.lang.Math;
// Main class
class EdPresso {
    public static void main( String args[] ) {
        System.out.println(Math.expm1(0));
    }
}

Case#3

// Load library
import java.lang.Math;
// Main class
class EdPresso {
    public static void main( String args[] ) {
        System.out.println(Math.expm1(Double.POSITIVE_INFINITY));
    }
}

Case#4

// Load library
import java.lang.Math;
// Main class
class EdPresso {
    public static void main( String args[] ) {
        System.out.println(Math.expm1(Double.NEGATIVE_INFINITY));
    }
}

What is Math.expm1() in Java?

Syntax

Parameters

Return value

Code