diff --git a/Scientific-Calc-UML as of 6:28:2021.png b/Scientific-Calc-UML as of 6:28:2021.png
deleted file mode 100644
index 8dd235e..0000000
Binary files a/Scientific-Calc-UML as of 6:28:2021.png and /dev/null differ
diff --git a/src/main/java/com/zipcodewilmington/scientificcalculator/CalculatorEngine.java b/src/main/java/com/zipcodewilmington/scientificcalculator/CalculatorEngine.java
index c83459f..a3669eb 100644
--- a/src/main/java/com/zipcodewilmington/scientificcalculator/CalculatorEngine.java
+++ b/src/main/java/com/zipcodewilmington/scientificcalculator/CalculatorEngine.java
@@ -58,4 +58,12 @@ public static Double squareRootY(Double firstNum, Double secondNum){
         return value;
         }
 
+        public static Double inverse(Double firstNum){
+        return 1 / firstNum;
+        }
+
+        public static Double signSwitch(Double firstNum){
+        return firstNum * (-1);
+        }
+
     }
diff --git a/src/test/java/com/zipcodewilmington/scientific_calculator/CalculatorEngineTest.java b/src/test/java/com/zipcodewilmington/scientific_calculator/CalculatorEngineTest.java
index fd83f0f..ee9dc2b 100644
--- a/src/test/java/com/zipcodewilmington/scientific_calculator/CalculatorEngineTest.java
+++ b/src/test/java/com/zipcodewilmington/scientific_calculator/CalculatorEngineTest.java
@@ -128,6 +128,19 @@ public void testSquareRootY(){
         Double actual = CalculatorEngine.squareRootY(firstNum, secondNumb);
         Assert.assertEquals(expected, actual);
     }
+    @Test
+    public void testInverse(){
+        Double expected = 0.125;
+        Double firstNum = 8.00;
+        Double actual = CalculatorEngine.inverse(firstNum);
+        Assert.assertEquals(expected, actual);
+    }
+    @Test
+    public  void testSignSwitch(){
+        Double expected = (-6.00);
+        Double firstNum = (6.00);
+        Double actual = CalculatorEngine.signSwitch(firstNum);
+    }
 }