diff --git a/src/main/c/Calculator/calculator.c b/src/main/c/Calculator/calculator.c
index a5d66a4..54d4c78 100644
--- a/src/main/c/Calculator/calculator.c
+++ b/src/main/c/Calculator/calculator.c
@@ -11,6 +11,11 @@ double modulus(double num1, double num2);
 double logarithm(double num);
 double potential(double base, double exponent);
 double squareRoot(double num);
+double square(double num);
+double sine(double angle);
+double cosine(double angle);
+double tangent(double angle);
+
 
 int main() {
     int choice, num1, num2, result;