diff --git a/src/main/java/stirling/software/SPDF/utils/GeneralUtils.java b/src/main/java/stirling/software/SPDF/utils/GeneralUtils.java
index 849aa697..045dc8b5 100644
--- a/src/main/java/stirling/software/SPDF/utils/GeneralUtils.java
+++ b/src/main/java/stirling/software/SPDF/utils/GeneralUtils.java
@@ -217,7 +217,7 @@ public class GeneralUtils {
         DoubleEvaluator evaluator = new DoubleEvaluator();
 
         // Validate the expression
-        if (!expression.matches("(?:abs|acos|asin|atan|average|ceil|cos|cosh|floor|ln|log|max|min|round|sin|sinh|sum|tan|tanh|random|[0-9n+\\-*/()%^ ])+")) {
+        if (!expression.matches("(?:abs|average|ceil|floor|max|min|round|sum|random|[0-9n+\\-*/()%^ ])+")) {
             throw new IllegalArgumentException("Invalid expression");
         }