3cos180°+5ctg270°-2tg0°+3tg180°-tg60°=

 3cos180° + 5ctg 270° - 2tg0 - sin 60° = 3*(-1) + 5*0 - 2*0 - √3/2 = -3 + 0 + 0  -√3/2=-3-√3/2