diff --git a/src/simplejavacalculator/Calculator.java b/src/simplejavacalculator/Calculator.java
index 5f016ac..0e204d1 100644
--- a/src/simplejavacalculator/Calculator.java
+++ b/src/simplejavacalculator/Calculator.java
@@ -47,6 +47,9 @@ private Double calculateBiImpl() {
             return num1 * num2;
         }
         if (mode.equals(BiOperatorModes.divide)) {
+            if (num2 == 0){
+                return NaN;
+            }
             return num1 / num2;
         }
         if (mode.equals(BiOperatorModes.xpowerofy)) {
@@ -92,6 +95,9 @@ public Double calculateMono(MonoOperatorModes newMode, Double num) {
             return Math.sqrt(num);
         }
         if (newMode.equals(MonoOperatorModes.oneDividedBy)) {
+            if(num == 0) {       
+                return NaN;         // This line of code handles division by zero to avoid infinity
+            }                         
             return 1 / num;
         }
         if (newMode.equals(MonoOperatorModes.cos)) {
diff --git a/src/simplejavacalculator/UI.java b/src/simplejavacalculator/UI.java
index 087bfb1..565f5d8 100644
--- a/src/simplejavacalculator/UI.java
+++ b/src/simplejavacalculator/UI.java
@@ -299,8 +299,14 @@ public void actionPerformed(ActionEvent e) {
          if (source == butabs)
             writer(calc.calculateMono(Calculator.MonoOperatorModes.abs, reader()));
 
-         if (source == butEqual)
-            writer(calc.calculateEqual(reader()));
+         if (source == butEqual){
+            Double result = calc.calculateEqual(reader());
+            if (Double.isNaN(result)){                   // it checks for math errors (like dividing by 0) and if there is one, it returns
+                text.setText("Invalid Operation");       // "invalid operation". If not, it returns the result
+            } else {
+                writer(result);
+            }
+         }
 
          if (source == butCancel)
             writer(calc.reset());