# GoLang – Find the order-one Bessel – Y1() Function – Examples & Explanation

`Y1()` function is used to find the order-one Bessel function of the second kind. The standard math package of Go programming language has `Y1()` function.

## Syntax of `Y1()` Function in Go

The syntax of `Y1()` function in Go Language is:

```func Y1(x float64) float64
```

Note: `float64` is a data type in Go language which has IEEE-754 64-bit floating-point numbers.
Special cases are:
```Y1(+Inf) = 0 Y1(0) = -Inf Y1(x < 0) = NaN Y1(NaN) = NaN```

## Parameters of `Y1()` Function in Go Language

`x ` – Where `x` is any Valid `float64` Input value. This parameter is required.

## Error Handling

If the `x ` parameter is not a number (numeric value) `Y1()` function returns an `error `.
If there is no argument (`x` – input value) passes to the function, then the compiler will produce an `error`.

## Return Value of `Y1()` Function in Go

`Y1()` function will return the order-one Bessel function of the second kind.

## GoLang `Y1()` Function Example 1

```package main

import "fmt"
import "math"

func main() {
var x float64
x = math.Y1(-9.8)
fmt.Println(x)
}
```

Output:
` NaN`

## GoLang `Y1()` Function Example 2

```package main

import "fmt"
import "math"

func main() {
var x float64
x = math.Y1(45.77)
fmt.Println(x)
}
```

Output:
` -0.06268204062757404`

## GoLang `Y1() ` Function Example 3

```package main

import "fmt"
import "math"

func main() {
var x float64
x = math.Y1(1)
fmt.Println(x)
}
```

Output:
` -0.7812128213002887`