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ANSWERS




               Chapter  1  Functions                        Exercise 1.2
                                                              1.  (b)  c, d        (c)  {1, 2, 3, 4, 5}
             Exercise 1.1                                        (d)  {a, b, c, d}   (e)  No
               1.  (a)  –9   (b)  7   (c)  0   (d)  0         2.  (a)   X     Y
               2.  (a)  (i)  3   (ii)  1   (iii) 0                  –2        3
                  (b)  (i)  24   (ii)  99                           –1
               3.  (a)  [–2, 6] or –2 < f(x) < 6                    0         1
                                                                    1
                      f(x )                                         2         7
                      6                                        (b)  {–2, –1, 0, 1, 2}
                                                               (c)  {1, 3, 7}
                                                               (d)  No
                                                              3.  (a)
                                                                             Y
                                 x
                    –1  0  3
                                                                    X        –5
                                                                             –3
                      –2
                                                                    1        –1
                (b)  [–1, 3] or –1 < f(x) < 3                       3        3
                                                                    5        5
                       f(x )
                                                                    7        7
                       3                                            9        11
                                                                             15
                                                               (b)  –1, 15
                                                               (c)  Yes
                                  x
                    –1  0       3                                            1
                                                              4.  No. f(0) = f(1) = 0,
                       –1                                                    2
                                                                 a
                                                                              1
                    9
                           9
                (c)  3 –  , 44  or –   < f(x) < 4             5.   1 + a 2  ; {g : 0 , y <  }
                    4      4                                                  2
                                                                  –1
                           f(x )                              6.  (a)  f  : x ⟼ x + 2, x ∈ R
                                                                   –1
                                                               (b)  f  : x ⟼  x – 1  , x ∈ R, x > 1
                           4
                                                                   –1
                                                               (c)  f  : x ⟼  x + 1, x > 0
                                                                   –1
                                                               (d)  g  : x ⟼ 3 +  x + 1 , x > –1
                                                               (e)  g  : x ⟼  x + 9 , x . –9
                                                                   –1
                                      x
                        –2  0     3                                      2 + 3x
                                                               (f)  h  : x ⟼   x   , x ≠ 0
                                                                   –1
                                                                   –1
                         –  9 _                                (g)  h  : x ⟼  2(x + 1)  , x ≠ 1
                           4                                             x – 1
                                                                      1 – x  1
                                                                –1
               4.  (a)  No   (b)  Yes     (c)  No             7.  f (x) =   2x – 1   ,   , x < 1
                                                                            2
                      1
               5.  (a)  1, 4,   , 64   (b)  4   (c)  R   +
                      2                                       9.  (a)   f(x )      (b)     f(x )
               6.  x + 2                                                    f                   f  –1
               7.  4 – x   2                                                  f  –1              f
               8.  (a)  cos (1 + x)   (b)  cos (cos x)                        x            0      x
                (c)  1 + cos x                                         0
               9.  (a)  1 – x  , –1 , x , 1   (b)  1 – x
                      2
                    2
                (c)  2x  – x 4
                    2
               10.  (a)  4x  – 6x + 1                          (c)     f(x )  f    (d)     f(x )  f
                (b)  2x  + 6x – 1                                             f –1               f  –1
                    2
                  (c)  4x – 9
                (d)  x  + 6x  + 14x  + 15x + 5                                 x                   x
                   4
                            2
                       3
                                                                       0                   0
               11.  (a)  6          (b)  25
                (c)  2a  – 4a + 9         (d)  4x  – 12x + 14
                    2
                                        2
                    2
                (e)  2x  + 4x + 9         (f)  x  + 10x  + 30
                                       4
                                            2
             268
       Answers STPM Math T S1.indd   268                                                               3/28/18   4:25 PM
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