# Scala - Math expm1() Method

The Scala Math 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.

### Syntax

```def expm1(x: Double): Double = java.lang.Math.expm1(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.

```import scala.math._

object MainObject {
def main(args: Array[String]) {
println(s"expm1(-1) = \${expm1(-1)}");
println(s"expm1(0) = \${expm1(0)}");
println(s"expm1(1) = \${expm1(1)}");
println(s"expm1(2) = \${expm1(2)}");
println(s"expm1(Double.NaN) = \${expm1(Double.NaN)}");
println("expm1(Double.PositiveInfinity) = "
+ expm1(Double.PositiveInfinity));
println("expm1(Double.NegativeInfinity) = "
+ expm1(Double.NegativeInfinity));
}
}
```

The output of the above code will be:

```expm1(-1) = -0.6321205588285577
expm1(0) = 0.0
expm1(1) = 1.718281828459045
expm1(2) = 6.38905609893065
expm1(Double.NaN) = NaN
expm1(Double.PositiveInfinity) = Infinity
expm1(Double.NegativeInfinity) = -1.0
```

❮ Scala - Math Methods

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