# Function asin Calculate the inverse sine of a value. For matrices, the function is evaluated element wise. ## Syntax ```js math.asin(x) ``` ### Parameters Parameter | Type | Description --------- | ---- | ----------- `x` | number | BigNumber | Complex | Array | Matrix | Function input ### Returns Type | Description ---- | ----------- number | BigNumber | Complex | Array | Matrix | The arc sine of x ## Examples ```js math.asin(0.5) // returns number 0.5235987755982989 math.asin(math.sin(1.5)) // returns number ~1.5 math.asin(2) // returns Complex 1.5707963267948966 -1.3169578969248166 i ``` ## See also [sin](sin.md), [atan](atan.md), [acos](acos.md)