tg(-675)=tg(-675+360+360)=tg(45)=1
cos(-570)=cos(-570+360+360)=cos(150)=-cos(-30)=cos(30)=-(sqrt3)/2
-ctg(150)=-ctg(-30)=ctg(30)=sqrt3
tg(-675)=tg(-675+360+360)=tg(45)=1
cos(-570)=cos(-570+360+360)=cos(150)=-cos(-30)=cos(30)=-(sqrt3)/2
-ctg(150)=-ctg(-30)=ctg(30)=sqrt3