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Basic Mathematics-II




                    Notes
                                          Example:

                                       
                                       1
                                    tan x dx
                                   Set
                                        -1
                                   f = tan x; dg = dx
                                   Deduce

                                               dx
                                          df      ;g   x
                                               
                                              1 x  2
                                   Get

                                                                           x
                                               1
                                                           1
                                                                     1
                                           tan x dx   1.tan x dx   tan x    
                                                                 x
                                            
                                                      
                                                                          1  x 2
                                                             1 d (x 2  )
                                                         1
                                                     x
                                                     tan x    
                                                             2 1  x 2
                                                             1
                                                         1
                                                                    2
                                                                   x
                                                     tan x   In (1+ )
                                                     x
                                                             2
                                          Example:
                                      2x
                                    xe dx
                                   Set
                                            2x
                                   f  = x; dg = e dx
                                   Deduce
                                                   e  2x
                                          df   dx ; g 
                                                    2
                                   Get
                                                          xe 2x  e 2x
                                             2x
                                                    2n
                                           xe dx   . x e  dx     
                                                           2    2
                                                  2x x  1 
                                                    
                                                  e      
                                                      2  4 
                                          Example:
                                      n
                                    sec x dx

                                               n
                                   Let G(n) =  sec x dx
                                            
                                   Set
                                                                 2
                                                        
                                          f   sec n  2  x   cos 2 n  ; x dg   sec x dx




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