diff --git a/main.rkt b/main.rkt
index 680795b..721c466 100644
--- a/main.rkt
+++ b/main.rkt
@@ -8,7 +8,11 @@
 (define (minus1 x)
   (sub1 x))
 
+(define (multiply1 x)
+  #f) ;buggy
+
 (module+ test
   (require rackunit)
   (check-equal? (plus1 1) 2)
-  (check-equal? (minus1 1) 0))
+  (check-equal? (minus1 1) 0)
+  (check-equal? (multiply1 1) 1))