ok so I think this is using chain rule again but i'm stuck at simplifying
y= ((1+cosx)/(sinx))^(-1)
i'm at
-1 (1+cosx/sinx) ^(-2) times (-sinx^2 - cos x +cos x^2)/sinx^2
and also
y=sec^(2) pi x
ok so there isn't any brackets around pix its just right beside sec^2 so i dont know how the chain rule would work?