# Function expm1 Calculate the value of subtracting 1 from the exponential value. For matrices, the function is evaluated element wise. ## Syntax ```js math.expm1(x) ``` ### Parameters Parameter | Type | Description --------- | ---- | ----------- `x` | number | BigNumber | Complex | Array | Matrix | A number or matrix to apply expm1 ### Returns Type | Description ---- | ----------- number | BigNumber | Complex | Array | Matrix | Exponent of `x` ### Throws Type | Description ---- | ----------- ## Examples ```js math.expm1(2) // returns number 6.38905609893065 math.pow(math.e, 2) - 1 // returns number 6.3890560989306495 math.log(math.expm1(2) + 1) // returns number 2 math.expm1([1, 2, 3]) // returns Array [ // 1.718281828459045, // 6.3890560989306495, // 19.085536923187668 // ] ``` ## See also [exp](exp.md), [log](log.md), [pow](pow.md)