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Basic Mathematics – I




                    Notes
                                                      =



                                                      =                       [Multiply and divide by a]


                                   Taking limit as  x   0, we have


                                                      =




                                   or                 =  a ∙ e ax + b  ∙ 1

                                                      =  ae ax + b

                                   2.6.1 Derivatives of Logarithmic Functions



                                   We first consider logarithmic function
                                   Let              y =  log x                                             …(i)
                                                y +  y =  log(x +  x)                                      …(ii)
                                                                 ( x and  y are corresponding small increments in x and y)

                                   From (i) and (ii), we get
                                                    y =  log(x +  x) –log x


                                                      =



                                                      =



                                                      =                                   [Multiply and divide by x]




                                                      =


                                   Taking limits of both sides, as  x   0, we get


                                                      =











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