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Exponents and radicals



           Example 5�10                                            x  n  æ  x  ö n

                                                       Generally,    n  =  ç  ÷ , where x, y and
           Simplify each of the following                          y    è  y  ø
           expressions:                                n are real numbers and y ≠ 0. This is a
                                                       power of a quotient.
                  3 20
           (a)
          FOR ONLINE READING ONLY
                  3 12                                 Example 5�11
                  a 28                                 Write each of the following expressions
                                                                          n
           (b)                                         in the form of  æ  x ö    . :
                  a 17                                               ç  ÷
                                                                     è  y  ø                         Mathematics for Secondary Schools
                                                           13 2   æ  13 ö  2
                  (0.47) 10                            (a)      =    ç  ÷
           (c)    (0.47) 6                                  9  2  è  9  ø

           Solution                                    (b)   (0.5) 4 4
                                                           (0.3)
           (a)   3 20  =  3 20 12
                          -
                 3 12                                  (c)   16
                     =  3 8                                 3 2

                 a 28                                  Solution
                          -
           (b)       = a 28 17
                 a 17                                     13 2   æ  13 ö  2
                     =  a 11                           (a)   9  2  =  ç  è  9  ÷  ø


           (c)   (0.47) 10  =  (0.47) 10 -  6              (0.5) 4  æ  0.5 ö  4
                  (0.47) 6                             (b)   (0.3) 4  =  ç  è  0.3 ø  ÷
                         =  (0.47 ) 4                                    2
                                                                       4
                                                       (c)   16  =  4 2  = æö
                                                                     ç÷
                                                                       3
                                                           3  2  3  2  èø
            When exponential numbers of different
            bases with the same exponents are          Exercise 5�3
            divided, the number can be expressed as    Simplify each of the following
            a single exponent. If a and b are any real   expressions:
            numbers such that b ≠  0, then:                x 5
                                                       1.
                                                            2
                            ´´´
                     a 4  =  aaaa                          x
                            ´´´
                     b 4   bbbb                             2 7000
                          aaaa                         2.
                        =   ´´´                             2 6998
                          bbbb                             625
                                                             4
                        =  æ  a ö 4                    3.   5
                          ç ÷
                          è b ø
                                                       4. 6  4  (2 a  2  4a ÷  a +  2  )


                                                    93
           Student's Book Form Two


                                                                                          11/10/2024   20:12:16
     MATHEMATIC F2 v5.indd   93                                                           11/10/2024   20:12:16
     MATHEMATIC F2 v5.indd   93
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