diff --git a/samples/pong/src/main.c b/samples/pong/src/main.c
index fc0e6e5..7795bb8 100644
--- a/samples/pong/src/main.c
+++ b/samples/pong/src/main.c
@@ -1,12 +1,9 @@
 #include <keys.h>
 #include <graphics.h>
+#include <math.h>
 
 #include <orca.h>
 
-extern float cosf(float);
-extern float sinf(float);
-extern float sqrtf(float);
-
 #define NUM_BLOCKS_PER_ROW 7
 #define NUM_BLOCKS 42 // 7 * 6