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?