Page 59 - Mathematics_Form_3
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Functions


                                  y                                1 
                                                       8.  y =    x +    for n ≤  x <  n +  1, where n  is an integer.
                                  1                                2 
                                    1 
                            y =    x +    for n ≤  x <  n +  1, where n  is an integer.
                 -4  -3  -2  -1   0  2   1  2  3 x
          FOR ONLINE READING ONLY
                                -1                     9.  The function  ()fx is defined as
                                                          follows:
                                -2                                    −  1 if x <  0
                                    }
                                                               ( ) =
                                                                     
                 Domain = { :xx∈  and                        fx      0 if x =  0
                                                                     
                 range  =   {y :  − 1  <  y  ≤  0}  .                 1 if x >  0
                                                       Find:  (a)  (3)f   and  ( 2)f −
               Exercise 2.6
                                                             (b) sketch the graph of  ()fx
               1.  Find the value of:                        (c) Find the range of  ()fx
                        23
                   (a)      4         (b)  0.1       10. Sketch the graph of

                                                               3 x for n − <
                                                           y =            1   x ≤  n  where n  is an integer.
                                                                
                   (c)  −     1.01    (d) 102     
                                   3 x for n − <
                               y =            1   x ≤  n  where n  is an integer.and state its
                                    
               In questions 2 to 8 sketch the graph       domain and range.
               each of the given functions:
               2.  f  ( )x =  2 forn  n −  1 ≤  x <  , n n  is a positive integer.
 f  ( )x =  2 forn  n − 1 ≤  x <  , n n  is a positive integer.  Absolute value functions
                                                      The absolute value of a number, say x,
               3.  f  ( )x =  3 forn  n − 1 ≤  x <  , n n  is a positive integer.
                                                      is its value without regarding its sign.
 f  ( )x =  3 forn  n −  1 ≤  x <  , n n  is a positive integer.  It is denoted by two vertical bars   .

                             x
                              , if 0 ≤
                            −  1, if x ≥  3  x <  x <  2  3  For instance, both  2 and  2− equal 2,
                          
      Mathematics for Secondary Schools  6.  ux =    0 if x <  0  symbol. For instance,  ()fx =  x which
                                4, if 2 ≤
               4.  fx =
                     ( )
                            x −
                                                      since both 2 and  2−  are 2 units away
                          
                          
                                                      from zero on the number line.
                          
                                                      An absolute value function is a function
                    ( ) =
                            
                                                      whose definition contains an algebraic
                1, where n
 gx  x x   for n ≤  x <  n +  5.   gx  x x   for n ≤  x <  n +  1, where n  is an integer.
                           is an integer.
 ( ) =
                                                      expression within the absolute  value
 
                    ()
                         
                                                      means
                            1 if x ≥
                                    0
                         
                                                                      
                                                               fx
                                                                 () =
                                                                      
                               x 
                                                                         x
                                                                       −
                                                                           if x <
                                                                                 0
                                                                      
                    1, where n
 gx    for n <  x ≤  7.  (a)  ( )gx =    for n <  x ≤  n +  1, where n  is an integer. x  if x ≥  0
 ( ) =
                n +
                              is an integer.
 x 
                                                       Example 2.26
                   (b)  ( )hx =    for n ≤  x <  n +  1, where n  is an integer.  x  and state
                              x 
                                                       Sketch the graph of  ()fx =
 ( ) =
 hx    for n ≤  x <  n +  1, where n  is an integer.  its domain and range
 x 
                                                    52                 Student\s Book Form Three
                                                                                          18/09/2025   09:59:01
     MATHEMATIC F3 SB.indd   52                                                           18/09/2025   09:59:01
     MATHEMATIC F3 SB.indd   52
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