к 93: -sin(2Pi-x)sinx-tgx*ctgx=sinx*sinx-tgx*ctgx=sin^2x-1=sin^2x-cos^2x-sin^2x=-cos^2x
К 93: -sin(2Pi-x)sinx-tgx*ctgx=sinx*sinx-tgx*ctgx=sin^2x-1=sin^2x-cos^2x-sin^2x=-cos^2x
93) -sinx*(-sinx) - tgx*(-ctgx)=sin^2x+ sinx/cosx * cosx/sinx = sin^2x