Page 24 - Module & More Matematik Tambahan Tg5
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Matematik Tambahan  Tingkatan 5  Bab 1  Sukatan Membulat

                                                                                         1
                   Lebar kad / Breadth of card                       (c)  Luas sektor BAC =   × (12)  × 1.23
                                                                                                 2
                   = j + 5 10                                           Area of sector BAC  2
                     15 10                                                             = 88.56 cm 2
                   =         + 5 10
                        2                                               Luas tembereng BAD
                   = 39.53 cm                                           Area of segment BAD                           1
                   ≈ 40 cm                                                1     2       1     2
               (b)  Luas kad tidak digunakan                            =  2  (18) (0.68) −  (18) sin38.94°
                                                                                        2
                   Area of unused card                                  = 8.34 cm 2
                                           
                   = 56 × 40 −    39.53 2   × 1.99  +                    Jumlah luas berlorek = 8.34 + 88.56         BAB
                                 2
                                                                                                    2
                                                                        Total shaded area
                                                                                           = 96.9 cm
                     1 15 10    2 (1.99)
                     2    2   
                   = 1244.88 cm 2
                                                                  4.  Rajah menunjukkan sebuah bulatan dan sektor
                                                                     berpusat  O. Diberi panjang lengkok  PS dan  QR
                                                                2017
                                                                     masing-masing ialah 3 cm dan 8 cm, dan  SR =
             3.  Rajah menunjukkan dua sektor, OAB berpusat O        9.5 cm.
               dan BAC berpusat A. Diberi OA = 18 cm dan AB =        The diagram shows a circle and a sector with centre
           2016
               12 cm.                                                O. Given the arc length PS and QR are 3 cm and 8 cm
               The diagram shows two sectors, OAB with centre O and   respectively, and SR = 9.5 cm.
               BAC with centre A. Given that OA = 18 cm and AB =
               12 cm.                                                                      Q
                                                                                     P
                              B         A
                                                                                 O
                                                                                     S
                                                                                           R
                                    C
                                 O                                   Cari/Find
                                                                     (a)  jejari bulatan dan sudut q dalam radian,
               Cari/Find                                                the radius and the angle q in radian,
               (a)  ∠BAC dalam radian,                               (b)  luas rantau berlorek itu.
                   ∠BAC in radian,                                      the area of the shaded region.
               (b)  perimeter rantau berlorek.
                   the perimeter of the shaded region.               (a)  3 = jq …. ➀
               (c)  luas rantau berlorek itu.                           8 = (j + 9.5)q …. ➁
                   the area of the shaded region.                       ➁ ÷ ➀                            Q
                                                                         8   j + 9.5               P
                            6                                              =                     j
               (a)   kos ∠A =                B                           3     j                    3 cm   8 cm
                            18                  12 cm  A                                       O
                      ∠A = 70.53°                                        5j = 9.5 × 3              S
                          = 1.23 rad                                     j = 5.7 cm                9.5 cm  R
               (b)  Panjang lengkok BC             C                     q =   3   = 0.53 rad
                   Arc length BC                                            5.7
                   = 12 × 1.23                  O                          = 30.37°
                   = 14.77 cm                                        (b)  Luas rantau berlorek = Luas  ∆OQR − Luas
                   ∠BOA = 180° − 2(70.53°)                                                   sektor POS
                         = 38.94° = 0.68 rad                            Area of shaded region =  Area OQR – Area of sector
                   Panjang lengkok BA = 18 × 0.68                         1                 POS  1
                                                                                                      2
                   Arc length BA      = 12.23 cm                        =  2  (9.5+5.7)  sin30.37° −  (5.7) (0.53)
                                                                                    2
                                                                                                2
                   Perimeter  = 12.23 + 14.77 + 12                      = 49.79 cm 2
                             = 39 cm

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