Find the exact value of the expression or state that it does not exist.
cos(sin^-1 ( sqrt(3)/ 5))



a.  In the function y=sin^-1(x), the expression sin^-1 x is defined as an angle in what interval? 


        [, ], by the definition of the function arcsin(x)  (which is exactly the same as  sin^(-1) (x) )



b.  Where does the terminal side of sin^-1 (sqrt(3)/5) lie? 


        In the first quadrant.



c.  Determine the value of cos(sin^-1 ( sqrt(3)/ 5)). 


        You are given that   = .


        Then  =  =  =  =  =  = .