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Exponents and radicals


             Example 5�27                              Example 5�29

                      5
             Express   1024  in its simplest form.      Express each of the following numbers
                                                       under a single radical sign:
             Solution
                                                       (a)  2 3           (b)  2 4
                                                                                3
             Write  1024 as a product of prime
                                                       Solution
          FOR ONLINE READING ONLY
             factors.                                  (a)  2 3  =  2 × 2 × 3
     Mathematics for Secondary Schools  Apply the fifth root on both sides to   Therefore,   2 3   =   12  .
             1024 = 2×2×2×2×2×2×2×2×2×2
                                                                    =   12
             obtain,
             5
               1024 =
                       2222222222×××××××××
                      5
                                                       (b)
                         5
                        2 ×
                            2
                       5
                             5
                     =
                                                                   3
                                                              3
                           1
                                5
                              2
                       2
                         5
                            ×
                                                                    =   32
                           5
                                                                    3
                         = ( ) ( ) 1 5                      2 4  =  2 × 2 × 2 × 4

                        =  22×                         Therefore,   2 4   =   32 .
                                                                           3
                                                                    3
                        =  4
                                 4
             Therefore,  1024 = �                       Exercise 5�7
                        5
                                                        1.  Simplify each of the following
           Example 5�28                                    expressions:
           Express each of the following numbers           (a)     169        (b)    729
           in its simplest form.
                                                           (c)                (d)
           (a)     20         (b)   3  54                        4  2048            4  2500
           Solution                                        (e)     1024       (f)   3  512
           (a)     20 =   2 2´´     5
                                                           (g)   3  343       (h)   3  1000
                          =  22´´    5                                                 t 4
                        2 =  5´                            (i)   3  729       (j)   5
                                                                                     81s 24
                        =  25 2 =  5´
           Therefore,  20  = 25=  .                     2.  Express each of the following
                                                           expressions in simplest form.
           (b)   = 54 = 3×3×3×2
                                ´´´
                        54 =
                       3
                               333 2
                             3
                         3
                  3
                                                           (a)     40        (b)    250
                                     2
                           ´´
                       =  3  333´ 3 3  54 =  3 333 2
                                     ´´´

                          3 =  3 = 2´  3  333´  3  2       (c)    6 1024     (d)   3 54
                                ´´
                          3
                       = 3 2  3 =  3  2´                   (e)   3  270      (f)   3  162
                      3
                               3
           Therefore,  54   3 2
                            =
                                                   102
                                                                            Student's Book Form Two
                                                                                          11/10/2024   20:12:27
     MATHEMATIC F2 v5.indd   102                                                          11/10/2024   20:12:27
     MATHEMATIC F2 v5.indd   102
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