Arrangement:
Let x = {0, 1, 2, 3, 4, 5} and activity * is characterized as
a * b = { ???? + ???? ???????? ???? + ???? < 6
???? + ???? − 6 ???????? ???? + ???? ≥ 0
Let us say, is the personality for the activity , if ae = a = e*a
That is a = – b or b = 6 – a, which shows a ≠ – b Since x = {0, 1, 2, 3, 4, 5} and
Backwards of a component a ∈ x, a ≠ 0, and a-1 = 6 – a.