WEEK 8
M: Completion of the proof of Fundamental Theorem of Arithmetic. Binary relations and functions.
      4.11. Remark. 4.7 -- 4.10 go through for polynomials. 
      5.1. Nebulous definition. Ordered pair <a,b>.
      5.2. Definition. Binary relation.
      5.3. Definition. Image R[A] and inverse image R^-1[A]. 
                                 R[A] = { y | (Ex \in A) <x,y> \in R }
                                 R^-1[A] ={ x | (Ey \in A) <x,y> \in R }  
      PROBLEMS FOR DISCUSSIONS  
W: Basic notions concerning binary relations. 
     5.4. Definition. Cartesian product A × B.
     5.6. Definition. Domain dom(R) and range rng(R) of a relation. Binary relations from A to B and binary relations on A.
     5.7. Definition. The identity relation id_A.
     5.8. Definition. Inverse relation R^-1 and composition of relations S o R.
     PROBLEMS FOR DISCUSSIONS: Book, p.108 Exercise 8, 9, 14, 15, 16; p.114 Exercise 18 and
                                                                                 p.141 Exercise 90, 92, 93      
F: Holiday.