diff --git a/code/Angabe5.hs b/code/Angabe5.hs
index 8da21b7..d45e268 100644
--- a/code/Angabe5.hs
+++ b/code/Angabe5.hs
@@ -97,6 +97,11 @@ instance Num Zahlraum_0_10 where
    (-) n n' = diff_r n n'
    (*) n n' = mult_r n n'
    fromInteger n = nat_to_roman (fromInteger n)
+   abs n = n
+   signum n
+      | n == F = F
+      | n == N = N
+      | otherwise = I
 
 add_r :: Zahlraum_0_10 -> Zahlraum_0_10 -> Zahlraum_0_10
 add_r n n'
@@ -127,12 +132,22 @@ mult_r n n'
 
 -- Aufgabe A.2
 
--- instance Eq Funktion where
---  ...
+instance Eq Funktion where
+   (==) f f' = (show f) == (show f')
 
--- instance Show Funktion where
---  ...
+instance Show Funktion where
+   show f =
+      let
+         result = drop 1 (show (build_pairs f N))
+      in
+      "{" ++ take ((length result) -1) result ++ "}"
 
+build_pairs :: Funktion -> Zahlraum_0_10 -> [(Zahlraum_0_10, Zahlraum_0_10)]
+build_pairs fkt arg
+   | arg == F && z == F = [(F, F)]
+   | otherwise = (arg, z) : (build_pairs fkt (arg + I))
+   where
+      z = (f fkt) arg
 
 -- Aufgabe A.3