# Function acsch Calculate the hyperbolic arccosecant of a value, defined as `acsch(x) = asinh(1/x) = ln(1/x + sqrt(1/x^2 + 1))`. For matrices, the function is evaluated element wise. ## Syntax ```js math.acsch(x) ``` ### Parameters Parameter | Type | Description --------- | ---- | ----------- `x` | number | Complex | Array | Matrix | Function input ### Returns Type | Description ---- | ----------- number | Complex | Array | Matrix | Hyperbolic arccosecant of x ### Throws Type | Description ---- | ----------- ## Examples ```js math.acsch(0.5) // returns 1.4436354751788103 ``` ## See also [asech](asech.md), [acoth](acoth.md)