A set of real numbers A, is called inductive if a) 1 is in A b) k in A implies k+1 is in A
Prove the following:
1. R is inductive
2. The set of positive real numbers is inductive
3. The set of positive real numbers unequal to 1/2 is inductive
4. The set of positive real numbers unequal to 5 is not inductive
5. Let A and B be inductive, then the intersection of A and B is inductive