(sin3/2a+cos3/2a)^2/[(sin3/2a+cos3/2a)*(sin3/2a-cos3/2a)]
=(sin3/2a+cos3/2a)/(sin3/2a-cos3/2a)
=(tan3/2a+1)/(tan3/2a-1)
=-tan(3/2a+45度)
(sin3/2a+cos3/2a)^2/[(sin3/2a+cos3/2a)*(sin3/2a-cos3/2a)]
=(sin3/2a+cos3/2a)/(sin3/2a-cos3/2a)
=(tan3/2a+1)/(tan3/2a-1)
=-tan(3/2a+45度)