diff --git a/src/trig_functions/trig_functions.c b/src/trig_functions/trig_functions.c
index 8b13789..8eec384 100644
--- a/src/trig_functions/trig_functions.c
+++ b/src/trig_functions/trig_functions.c
@@ -1 +1,14 @@
+#include "trig_functions.h"
+#include <math.h>
 
+double calculate_sin(double angle) {
+    return sin(angle);
+}
+
+double calculate_cos(double angle) {
+    return cos(angle);
+}
+
+double calculate_tan(double angle) {
+    return tan(angle);
+}