Question

упростите ctg x-sinx/1-cosx
sin(-a)cos(-a)(tga+ctga)

Answer 1

1
(cosx/sinx -sinx):(1-cosx)=(sinxcosx-sinx)/sinx:(1-cosx)=
=sinx(cosx-1)/sinx*1/(1-cosx)=-1
2
-sina*cosa*(sina/cosa+cosa/sina)=-sinacosa*(sin²a+cos²a)/(sinacosa)=-1