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(c)  When v = 0,                                    (ii)  Total distance travelled
                            4t – t  + 16  = 0                                        1              3
                                2
                                                                                                             u
                                                                                                    2
                                                                                     2
                                    t  = 2 + 2√5                                 =  t  – 4t + 3 dt +  u  t  – 4t + 3 dt  +
                                    t  = 2 – 2√5   (rejected)                      0   4          1
                            So, P = 2 + 25 s.                                        t  – 4t + 3 dt
                                                                                     2
                                                               [2]                 3 3   2    1    3        3
                                                                                             4 u3
                                                                                                       2
                         (d)  s =   4t – t  + 16 dt                              = 3 t 3  –  4t   + 3t  +   t 3  – 2t  + 3t 4 u  +
                                    2
                                                                                        2
                                                                                                            1
                                                                                              0
                               4t 2  t 3                                           3 t 3  – 2t  + 3t 4 4
                                                                                         2
                              =    –   + 16t + d                                    3
                                2   3                                              4   4  4   3
                                   t
                                    3
                              = 2t  –   + 16t + d                                =  3   +   +   3
                                 2
                                                                                       3
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                                   3
                            When t = 0, s = 0.                                   = 4 m
                                                                                                                [3]
                                  0
                                   3
                            2(0)  –   + 16(0) + d = 0                   4.  (a)  a = 6t – 10
                                2
                                  3         d = 0                            When a = 0,
                                    3
                                   t
                            s = 2t  –   + 16t                                6t = 10
                                2
                                                                                 5
                                   3                                          t =   s
                            When t = 5,                                          3                              [2]
                                     5
                                      3
                            s = 2(5)  –   + 16(5)                         (b)    dv   = 0
                                  2
                                     3
                                                                                dt
                                 1
                              = 88  m                                        6t – 10 = 0
                                 3                             [4]
                                                                                     5
                                                                                  t  =  s
                                                                                     3
                       3.  (a)  (i)  When t = 0, v = 3.
                                0  – 4(0) + s = 3                            s =   3t  – 10t – 32 dt
                                                                                   2
                                 2
                                s = 3                                           3t 3  10t 2
                                                               [1]             =   3   –   2   – 32t + c
                            (ii)  v = t  – 4t + 3                              = t  – 5t  – 32t + c
                                   2
                                                                                    2
                                                                                3
                                  t  – 4t + 3 , 0                            When t = 0, s = 0.
                                   2
                                (t – 3)(t – 1) , 0                           0  – 5(0)  – 32(0) + c = 0
                                                                                    2
                                                                              3
                                1 < t < 3                                                   c = 0
                                                               [2]                 3      2
                                                                                               5
                                                                                 5
                                                                                        5
                            (iii)  a = 2t – 4                                s =  1 2   – 5 1 2   – 32 1 2
                                                                                               3
                                                                                        3
                                                                                 3
                                2t – 4 . 0                                        1690
                                   2t . 4                                      = –   27
                                    t . 2
                                                               [1]           Distance from O =  1690  m
                                                                                              27
                         (b)  (i)                                                                               [5]
                                 y
                                4
                                3
                                2
                                1
                                0                             x
                                      1    2   3    4    5
                               –1
                                                               [2]
                                                                                                     Answers    211




         Answers Add Math.indd   211                                                                             14/03/2022   12:29 PM
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