Added squareRootFunction for calculating square roots

src/main/c/main_taschenrechner.c

@@ -22,6 +22,13 @@ int divide(int a, int b) {
     return a / b;
 }
 
+// Square root function
+double squareRootFunction(double x) {
+    // Using the sqrt function from math.h
+    return sqrt(x);
+}
+
+//..
 // Trigonometric functions
 double sineFunction(double angle) {
     // Convert degrees to radians for trigonometric functions

src/main/c/taschenrechner.h

@@ -9,6 +9,10 @@ int multiply(int a, int b);
 
 int divide(int a, int b);
 
+// Square root function
+double squareRootFunction(double x);
+
+//..
 // Trigonometric functions
 double sineFunction(double angle);