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→     →                                            11    11
                         (c)    RT = k QO                                        = –   p +   r                  [2]
                                     1                                              5    5
                                     1( )
                              –   1  p = k –   2  p                           →  →  →
                               3        3                                 (c)  RS = PS – PR
                                k  =   1                                           11    11
                                 1  2                                            = –   5  p +   5  r – (–p + r)
                               →     →                                              6    6
                               RT = k QO                                         = –   5  p +   5  r
                                    2
                                    2( )
                               –   1  s = k –   1  s                          PR:RS
                               6        3                                     –p: –   6  p
                                                                                   5
                                k  =   1                                      PR:RS = 5:6                       [3]
                                2
                                    2
                                k =   1                                       →  →     →
                                    2                                     (d)  TR = TO + OR
                                                                                               )
                                                                                      (
                             Scalar multiples of one another.                    = –   1 11 r –   6  p  + r
                                    →     →                                         3 5     5
                             Vectors  RT and QO are parallel.   [2]              =  4  r +   6  p
                                →  →      →                                       15   15
                     11  (a)  (i)  OS = OQ + QS                                →    →
                                   = q + 3t                    [1]            OQ = mTR
                                                                                      6
                                →    2                                        3  p = m ( )
                                                                                        p
                            (ii)  OP =   q                     [1]            5       15
                                     5                                         m = 1.5
                             →  →     →
                                                                              →
                                                                                    →
                         (b)  PR = PO + OR                                    OQ = nTR
                                  →   2  →
                                                                                      4
                                = PO +   OS                                      2  r = n ( )
                                                                                       r
                                      5                                        5     15
                                = –  2  q +   2  (q + 3t)                       n = 1.5
                                   5    5                                     Scalar multiples of one another.
                                  6
                                =   t                                                →     →
                                  5                                           Vectors  TR and OR are parallel.   [4]
                                  6
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                              k =
                                                               [2]
                                  5                                        Transformations
                         (c)  PR :QS
                                                                           –11
                             6                                        1   ( )                                   [2]
                               t :3t                                       11
                             5
                               6 :15                                  2   p(2, 3)                               [2]
                             Area of ΔOPR:Area of ΔOQS                3   (a), (b) and (c)
                             36:225                            [2]                       y
                         (d)  Area of ΔOPR:Area of ΔOQS                                 8
                             20 cm :125 cm 2                                            7
                                 2
                             Area of PRSQ                                               6
                             = 125 – 20                                                 5
                             = 105 cm 2                        [2]                      4  Q
                                                                                        3
                                →  →     →                                              2
                     12  (a)  (i)  PR = PO + OR                             S           1      P
                                   = –p + r                    [1]                                           x
                                 →   →    →                            –8  –7 –6  –5 –4  –3  –2 –1 0  1  2 3 4 5 6 7 8
                            (ii)  OQ = OP + PQ                              R          –1
                                                                                       –2
                                     →    2  →                                         –3
                                   = OP +   PR
                                          5                                            –4
                                         2                                             –5
                                   = p +   (– p + r)
                                         5                                             –6
                                                                                       –7
                                   =  3  p +   2  r            [2]                     –8
                                     5     5                                                                       [7]
                             →  →     →
                         (b)  PS = PO + OS
                                = – p +  11 r –   6  p
                                      5    5




                                                                                                     Answers    177







         Answers.indd   177                                                                                      15/03/2022   11:08 AM
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