jawaban poin i dan j brapa ya??

i. √((1+cosy) - (1-c0sy)/(1-cos^2y)(1+cosy)
  = √2cos y / (1-cos^2 y)
= √2cos y / sin^2 y
= (1/sin y)  √2 cos y

j. ((sin^2 x -sin^2y) + (cos^2 x -cos^2 y) / ((cosx -cos y)(sinx + siny)
  = ((sin^2 x + cos^2 y - (sin^2 y + cos^2y) / ((cos x - cosy )(sinx+siny)
 = (1 - 1) / (cos x-cosy)(sin x + siny)
 = 0

[tex]i. \sqrt{ \frac{1+cos y-1+cosy}{(1-cosy)(1+cosy)} } = \sqrt{ \frac{2 cos y}{1-cos^{2} y } } = \sqrt{ \frac{2 cos y}{sin^{2} y } }[/tex]
[tex]j. \frac{sin x^{2} - sin^{2}y + cos^{2}x - cos^{2} y }{(cosx-cosy)(sinx+siny)} = \frac{0}{(cosx-cosy)(sinx+siny) = 0}[/tex]