Find an algebraic expression for cos2sin1 x Do not simplifyS
     Find an algebraic expression for cos(2sin^-1 x). Do not simplify. 
  
  Solution
cos(2A)=1-2(sinA)2
cos(2sin-1(x))=1-2(sin(sin-1(x)))2
cos(2sin-1(x))=1-2(x)2
cos(2sin-1(x))=1-2x2

