From e2d86aa685685a03e8ab2b2bddebb4d3db17e7f7 Mon Sep 17 00:00:00 2001
From: Shaun Moss <shaun@astromultimedia.com>
Date: Wed, 26 Oct 2022 17:06:09 +1000
Subject: [PATCH] Added hyperbolic trig functions, which were needed for my
 DecimalComplex class.

---
 .gitignore             |  4 ++++
 DecimalEx/DecimalEx.cs | 26 ++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/.gitignore b/.gitignore
index b248083..c004aef 100644
--- a/.gitignore
+++ b/.gitignore
@@ -347,3 +347,7 @@ healthchecksdb
 
 # Backup folder for Package Reference Convert tool in Visual Studio 2017
 MigrationBackup/
+
+# JetBrains settings
+.idea
+
diff --git a/DecimalEx/DecimalEx.cs b/DecimalEx/DecimalEx.cs
index 9adaa65..30b0cd7 100644
--- a/DecimalEx/DecimalEx.cs
+++ b/DecimalEx/DecimalEx.cs
@@ -629,5 +629,31 @@ public static decimal Remainder(decimal d1, decimal d2)
 
             return d1;
         }
+        
+        /// <summary>
+        /// Hyperbolic sine.
+        /// </summary>
+        /// <param name="x">The hyperbolic angle.</param>
+        /// <returns>The hyperbolic sine of the given angle.</returns>
+        public static decimal Sinh(decimal x) => (Exp(x) - Exp(-x)) / 2;
+
+        /// <summary>
+        /// Hyperbolic cosine.
+        /// </summary>
+        /// <param name="x">The hyperbolic angle.</param>
+        /// <returns>The hyperbolic cosine of the given angle.</returns>
+        public static decimal Cosh(decimal x) => (Exp(x) + Exp(-x)) / 2;
+
+        /// <summary>
+        /// Hyperbolic tangent.
+        /// </summary>
+        /// <param name="x">The hyperbolic angle.</param>
+        /// <returns>The hyperbolic tangent of the given angle.</returns>
+        public static decimal Tanh(decimal x)
+        {
+            decimal a = Exp(x);
+            decimal b = Exp(-x);
+            return (a - b) / (a + b);
+        }
     }
 }