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Unit 12: General Convergence Theorems




          Then each f  is bounded and                                                           Notes
                   n
                 f     f at each point
                  n
          Since {f } is an increasing sequence of bounded functions such that f     f on E
                n                                               n
                 By the monotone convergence theorem


                  lim f   f
                  n   n
                     E   E
                 For given   > 0   a positive integer N such that


                    f n  f   for n  N
                           2
                   E   E

                    f  f
                        N
                           2
                   E  E
                       f   f
                   2       N  2
                      E   E

                   (f f )
                      N
                          2
                  E
                 Choose
                           2N

                 If mA <  , then we have

                                     f     (f f ) f
                                       =      N   N
                                    A    A

                                          (f f )  f
                                       =      N    N
                                         A       A

                                          (f f )  N as f  N
                                              N         N
                                         E       A

                                       <    NmA
                                         2

                                       <    N
                                         2

                                       <    N
                                         2    2N


                                       =
                                         2  2
                                       =




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