In: Advanced Math
Define multiplication on ℤ? by ? ⊙ ? = ? where ? is the remainder when the product ?? is divided by ?.
(a) Show that this operation is commutative.
(b) Show that this operation is associative.
(c) Show that there is an identity element for this operation.
(d) Show that for ? = 5, the set of non-zero elements forms a group under multiplication.
(e) Show that for ? = 6, the set of non-zero elements does not form under multiplication.