# Java Math - expm1() Method

The Java expm1() method returns e raised to the power of specified number minus 1, i.e., ex-1. Please note that e is the base of the natural system of logarithms, and its value is approximately 2.718282. In special cases it returns the following:

• If the argument is NaN, the result is NaN.
• If the argument is positive infinity, then the result is positive infinity.
• If the argument is negative infinity, then the result is -1.0.
• If the argument is zero, then the result is a zero with the same sign as the argument.

### Syntax

```public static double expm1(double x)
```

### Parameters

 `x` Specify the exponent of e.

### Return Value

Returns e raised to the power of specified number minus 1, i.e., ex-1.

NA.

### Example:

In the example below, expm1() method is used to calculate e raised to the power of specified number minus one.

```public class MyClass {
public static void main(String[] args) {
System.out.println(Math.expm1(2));
System.out.println(Math.expm1(-2));
System.out.println(Math.expm1(1.5));
System.out.println(Math.expm1(-1.5));
}
}
```

The output of the above code will be:

```6.38905609893065
-0.8646647167633873
3.481689070338065
-0.7768698398515702
```

❮ Java Math Methods

5