The asin()
method calculates the arcsine (inverse of sine) of the specified angle and returns it.
Example
let value = Math.asin(1);
console.log(value);
// Output: 1.5707963267948966
asin() Syntax
The syntax of the Math.asin()
method is:
Math.asin(angle)
Here, asin()
is a static method. Hence, we are accessing the method using the class name, Math
.
asin() Parameter
The asin()
method takes a single parameter:
angle
- in radians whose arcsine is to be calculated
Note: The value of angle
should be between -1 and 1.
asin() Return Value
The asin()
method returns:
- arcsine value of the
angle
- NaN (Not a Number) if the argument is either non-numeric or greater than 1 or less than -1
Example 1: Math.asin() with argument between -1 and 1
// arcsine of negative number
let number1 = Math.asin(-1);
console.log(number1);
// arcsine of positive number
let number2 = Math.asin(0.5);
console.log(number2);
// Output:
// -1.5707963267948966
// 0.5235987755982989
In the above example, the Math.asin()
method computes the arcsine of
-1
(negative number) - results in -1.57079632679489660.5
(positive number) - results in 0.5235987755982989
Example 2 : Math.asin() for other Argument not in the range -1 and 1
// argument less than -1
let number1 = Math.asin(-100);
console.log(number1);
// Output: NaN
// argument greater than 1
let number2= Math.asin(32);
console.log(number2);
// Output: NaN
Here, we get NaN
as output because both the arguments, -100 and 32, are not in the range -1 and 1.
Example 3: Math.asin() with Non-Numeric Argument
let string = "Harry";
// asin() with a string argument
let value = Math.asin(string);
console.log(value);
// Output:
// NaN
In the above example, we have tried to calculate the arcsine of the string "Harry"
. That's why we get NaN as the output.
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