# Java.lang.Math.asin() Method

## Description

The java.lang.Math.asin(double a) returns the arc sine of an angle, in the range of -pi/2 through pi/2.Special cases −

• If the argument is NaN or its absolute value is greater than 1, then the result is NaN.

• If the argument is zero, then the result is a zero with the same sign as the argument.

A result must be within 1 ulp of the correctly rounded result. Results must be semi-monotonic.

## Declaration

Following is the declaration for java.lang.Math.asin() method

```public static double asin(double a)
```

## Parameters

a − the value whose arc sine is to be returned.

## Return Value

This method returns the arc sine of the argument.

NA

## Example

The following example shows the usage of lang.Math.asin() method.

```package com.tutorialspoint;

import java.lang.*;

public class MathDemo {

public static void main(String[] args) {

// get a variable x which is equal to PI/2
double x = Math.PI / 2;

// get the arc sine of x
System.out.println("Math.asin(" + x + ")=" + Math.asin(x));
}
}
```

Let us compile and run the above program, this will produce the following result −

```Math.asin(0.027415567780803774)=0.02741900326072046
```
java_lang_math.htm