Page 20 - Spotlight A+ Form 4 & 5 Mathematics KSSM
P. 20

Form
            4          Mathematics   Chapter 5 Network in Graph Theory


               Represent information in the form of            Solution:
               networks                                               Langkawi      Kota Kinabalu
                                                                           Kota Bharu
                   Example 18                                         Pulau           Sibu Tawau
                                                                      Pinang       Kuching
               The diagram below shows some roads in an area.
                                                                       Kuala
                                                                       Lumpur   Johor Bahru

                                                               Try question 19 in Formative Zone 5.1
                     ©PAN ASIA PUBLICATIONS
                                                                 Example 20
                                                              Five friends Asiah, Khairul, Natifah, Roslan and
                                                              Zeti made conversation by video calls in the
               By using the road junction as vertex and the road   following situation.
        CHAP.  as edge, draw an undirected graph to represent
         5     the network of the roads.                       Asiah called Khairul and Roslan but not Natifah
                Solution:                                      or Zeti. Zeti only called Roslan and Natifah. Zeti
                                                               had never called Khairul although Khairul always
                                                               called Zeti. Often Natifah and Roslan will call
                                                               one another as Khairul and Natifah.
                                                              Draw a directed graph to represent the
                                                              conversation by video calls described in the
                                                              situation.
                                                               Solution:
                                                                                     Natifah
                 Try question 18 in Formative Zone 5.1
                                                                       Khairul

                   Example 19                                                            Zeti

               The diagram below shows some locations of               Roslan     Asiah
               airports in Malaysia.
                                                               Try question 20 in Formative Zone 5.1
                       Langkawi       Kota Kinabalu
                             Kota Bharu
                                        Sibu                  Solve problems involving networks
                        Pulau             Tawau
                        Pinang      Kuching
                                                                 Example 21
                        Kuala
                        Lumpur   Johor Bahru                  The diagram below shows a network of roads
                                                              connecting five places A, B, C, D and E.
               A company Air X scheduled 10 flights on a day
               as follows.                                                     200   D

                      •  Pulau Pinang to Johor Bahru                      B    340  C 100  270
                      •  Kuching to Tawau                               400     120
                      •  Tawau to Kuching
                      •  Kuching to Kuala Lumpur                          A       350      E
                      •  Kota Kinabalu to Kuala Lumpur
                      •  Kuala Lumpur to Langkawi             The weights stated on each edge represent the
                      •  Langkawi to Pulau Pinang             distances, in m, between two places. A path is
                      •  Johor Bahru to Sibu                  a route along the edges of the graph from one
                      •  Pulau Pinang to Kota Bharu           vertex to the other vertices without repeating any
                      •  Kuala Lumpur to Kuching              one vertex.
                                                              By listing down all the possible paths, determine
               Draw a directed graph to represent the information   the shortest path from A to C and state its length.
               of the flights.



               100                                                                           5.1.4  5.1.5




         ENG05 Spotlight Matematik F4.indd   100                                                       14/01/2021   9:56 PM
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