Sin x*cos y=0 cos x*sin y=-1

Можно так [latex] left { {{sinxcosy=0} atop {cosxsiny=-1}} ight. left { {{sinxcosy+cosxsiny=-1} atop {sinxcosy-cosxsiny=1}} ight. left { {{sin(x+y)=-1} atop {sin(x-y)=1}} ight.left { {{x+y=- frac{ pi }{2}+2 pi n,n in Z } atop {x-y=frac{ pi }{2}+2 pi n,n in Z }} ight. [/latex][latex]left { {{2x=4 pi n,n in Z } atop {2y=- pi }} ight. left { {{x=2 pi n,n in Z } atop {y=- frac{ pi }{2} }} ight. [/latex]