Cos 4455° - cos (-945°) + tg 1035° - ctg (-1500°)

Question

Cos 4455° - cos (-945°) + tg 1035° - ctg (-1500°)

Answer 1

Cos(360*12+135)-cos(3*360-135)+tg(180*5+135)+ctg(180*9-120)=
=cos135-cos125+tg135-ctg120=tg(180-45)-ctg(180-60)=-tg45+ctg60=
=-1+1/√3