 # JavaScript Math acosh()

The `acosh()` method computes the hyperbolic arc-cosine of the specified number and returns it.

### Example

``````// hyperbolic arc-cosine of 5
let number = Math.acosh(5);
console.log(number);

// Output: 2.2924316695611777``````

## acosh() syntax

The syntax of the `Math.acosh()` method is:

``Math.acosh(number)``

Here, `acosh()` is a static method. Hence, we are accessing the method using the class name, `Math`.

## acosh() Parameter

The `acosh()` method takes a single parameter:

• `number` - a positive value whose hyperbolic arc-cosine is to be calculated

## acosh() Return Value

The `acosh()` method returns:

• hyperbolic arc-cosine of the given positive argument `number`
• NaN (Not a Number) for zero, negative and non-numeric argument

## Example 1: JavaScript Math.acosh() with Positive Numbers

``````// hyperbolic arc-cosine of an integer
let result1 = Math.acosh(32);
console.log(result1);

// hyperbolic arc-cosine of a floating-point number
let result2 = Math.acosh(4.5);
console.log(result2);

// Output:
// 4.158638853279167
// 2.1846437916051085``````

In the above example, we have used the `Math.acosh()` method with

• `32` (integer value) - results in 4.158638853279167
• `4.5` (floating-point value) - result in 2.1846437916051085

## Example 2: Math.acosh() with Zero and Negative Numbers

``````// hyperbolic arc-cosine of a negative number
let result1 = Math.acosh(-12.5);
console.log(result1);
// Output: NaN

// hyperbolic arc-cosine of zero
let result2 = Math.acosh(0);
console.log(result2);
// Output: NaN``````

In the above example, we have used the `acosh()` method with a negative number and zero. For both values, we get NaN as output.

Note: We can only use the `acosh()` method with positive numbers.

## Example 3: Math.acosh() with Non-Numeric argument

``````let string ="Harry";

// acosh() with a string argument
let value = Math.acosh(string);
console.log(value);

// Output: NaN``````

In the above example, we have used the `acosh()` method with the string `"Harry"`. Hence, we get NaN as output.