Page 19 - Trigonometry
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Example 6:

        Derivative of an inverse trigonometric function. Let,

                                            −1
                                     = sin (  )
        Then
                                               −1
                         sin(  ) = sin[sin (  )] =   


        Differentiating,
                                                   
                                    sin(  ) =          
                                                    

                                               
                                 cos(  )        = 1
                                               
        Dividing by cos(θ),

                                   1                 1
                            =            =
                               cos(  )       √1 − sin (  )
                                                         2
        This becomes,
                                              1
                                      =
                                         √1 −      2
        Leaving,

                                     −1             1
                                 sin (  ) =                                         1
                                                 √1−   2


        As you can see x < 1, to verify this result consider three
        test values for    = 0.49, 0.265, 0.857. Set calculator

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