# Function asech Calculate the hyperbolic arcsecant of a value, defined as `asech(x) = acosh(1/x) = ln(sqrt(1/x^2 - 1) + 1/x)`. For matrices, the function is evaluated element wise. ## Syntax ```js math.asech(x) ``` ### Parameters Parameter | Type | Description --------- | ---- | ----------- `x` | number | Complex | Array | Matrix | Function input ### Returns Type | Description ---- | ----------- number | Complex | Array | Matrix | Hyperbolic arcsecant of x ## Examples ```js math.asech(0.5) // returns 1.3169578969248166 ``` ## See also [acsch](acsch.md), [acoth](acoth.md)