# GoLang – Find Inverse of Sine – Asin() Function – Examples & Explanation

`Asin()` function is used to find the inverse of a sine in Go language. The inverse of a sine is also known as arcsine.

## `Asin()` Function in Go Language

`math.Asin()` exists is Standard math Library of Go Programming Language. The purpose of this function is to calculate arcsine or the inverse of the sin of any given number (`x` – parameter) within the range of `-1` and `1`.

## `Asin()` Function Syntax in Go Language

The syntax of `Asin()` function in GoLang is

Note: `float64` is a data type in go language which has IEEE-754 64-bit floating-point numbers.
Special cases are:
`Asin(±0) = ±0 Asin(x) = NaN if x < -1 or x > 1`

## GoLang `Asin()` Function Parameters

`x` – Any valid Golang number (positive or negative within the range of `-1` and `1`). This parameter is required.
Note: If the `x` parameter is not a number or greater than `1`, `Asin()` function will return an `error`.

## GoLang `Asin()` Function Return Value

`Asin()` function will return a floating point number (a value of the inverse of sine in radians).

## GoLang `Asin()` Function Example 1

Output:
`-1.5707963267948966`

Output:
`0`

## GoLang `Asin()` Function Example 3

Output:
`1.5707963267948966`

Note: The unit of output is radian.