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if tanA+sinA=m and tanA-sinA=n,prove that (m*m-n*n)(m*m-n*n)=16mn

tanA + sinA = m 
        tanA - sinA = n
(m*m - n*n)(m*m - n*n) 
    = (((tan2A + 2tanAsinA + sin2A)) - (tan2A+2tanAsinA+sin2A)*    
      ((tan2A+2tanAsinA+sin2A)) -  (tan2A+2tanAsinA+sin
     =(tan2A+2tanAsinA+sin2A-tan2A-2tanAsinA-sin2A)*(tan2A+2tanAsinA+sin2A-
      tan2A-2tanAsinA-
    =4tanAsinA*4tanA
   =16mn


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