Page 11 - ALGEBRA STRUCTURE cyclic group BY MIFTAHUL JANNAH (4193311004) MESP2019
P. 11

m
               Let m = smallest positive integers so that a = e
                                                      
               Take  any  b ∈ G =< a > then    =    , for  a n ∈ Z,  according  to  the  division  algorithm  then
               ∃ ! q, r ∈ Z ∋ n = mq + r, with 0 ≤ r < m, so that it is obtained

                                                      r
                                               q r
                     n
                                     m q r
               b = a = a  qm+r  = (a ) a = e a = a
               So ∀ b ∈ G ∃ r ∈ Z ∋ b = a  with 0 ≤ r < m
                                          r
                                                              2
                                                          1
                                                       0
               So that the G elements can be written : {a , a , a , … , a m−1 }
               The contradiction arises that G has infinite elements
                                              k
                                                   h
               So the right reliance is wrong a = a → k = h

               Example 6

                  = {0,1,2,3,4,5} with addition operation of modulo 6.
                 6
               Is     a cyclic group? If yes, specify the generator. By using Cayley table it can be shown that     is
                   6
                                                                                                          6
               a cyclic group with generator 1 and 5

               Proof

                Cayley table in set   
                                    6
                 +   0       1     2      3     4     5
                   6

                 0     0     1     2      3     4     5

                 1     1     2     3      4     4     0

                 2     2     3     4      5     0     1


                 3     3     4     5      0     1     2

                 4     4     5     0      1     2     3

                 5     5     0     1      2     3     4



               By looking the table above, so it is obtained :


                   1.  The first axiom (closed property) is satisfied because all operation result are in set    .
                                                                                                       6




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