Question

Show that the set of odd integer is not a group under addition

Answer 1

Answer:

injective (and hence bijective) assignments. I.e., |Perm(X)| = n!. [4] Give two reasons why the set of all odd integers does not form a group under the operation of addition. One reason is that + is not a binary operation on the set of odd integers, since the sum of any two odds is even.