[Term Entry] C# Math-functions: Acosh() (#7997)

* [Term Entry] C# Math-functions: Acosh()

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Author: ksuraev

content/c-sharp/concepts/math-functions/terms/acosh/acosh.md

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+---
+Title: 'Acosh()'
+Description: 'Returns the inverse hyperbolic cosine of a specified number.'
+Subjects:
+  - 'Computer Science'
+  - 'Web Development'
+Tags:
+  - 'Functions'
+  - 'Math'
+  - 'Methods'
+  - 'Numbers'
+CatalogContent:
+  - 'learn-c-sharp'
+  - 'paths/computer-science'
+---
+
+The **`Math.Acosh()`** method returns the inverse hyperbolic cosine (also known as hyperbolic arccosine) of a specified number. It computes the value whose hyperbolic cosine equals the given number.
+
+## Syntax
+
+```pseudo
+Math.Acosh(number);
+```
+
+**Parameters:**
+
+- `number`: A double-precision floating-point value greater than or equal to `1`, for which to compute the inverse hyperbolic cosine.
+
+**Return value:**
+
+- The inverse hyperbolic cosine of the specified number in radians as a `double`.
+- `NaN` if the input is less than `1` or `NaN`.
+
+## Example: Basic Usage of `Math.Acosh()`
+
+This example calculates the inverse hyperbolic cosine of a number using `Math.Acosh()` and displays the result in radians:
+
+```cs
+using System;
+
+public class Example
+{
+  public static void Main()
+  {
+    double number = 1.5;
+    double result = Math.Acosh(number);
+    Console.WriteLine($"Math.Acosh({number}) = {result} radians");
+  }
+}
+```
+
+This example outputs the following:
+
+```shell
+Math.Acosh(1.5) = 0.9624236501192069 radians
+```
+
+## Codebyte Example
+
+In this example, the `Math.Acosh()` method is used to calculate the inverse hyperbolic cosine of a specified number in radians and degrees:
+
+```codebyte/csharp
+using System;
+
+public class Example {
+  public static void Main() {
+    double number = 100.0;
+
+    // Calculate Acosh in radians
+    double resultRadians = Math.Acosh(number);
+
+    // Convert radians to degrees
+    double resultDegrees = resultRadians * (180.0 / Math.PI);
+
+    // Display results
+    Console.WriteLine($"Math.Acosh({number}) = {resultRadians} radians");
+    Console.WriteLine($"Math.Acosh({number}) = {resultDegrees} degrees");
+  }
+}
+```