2sin870°+√12•cos570°-tg60°

Question

2sin870°+√12•cos570°-tg60°

Answer 1

2sin870+√12cos570-tg²60=2sin(π/2+60)+2√3cos(3π/2-60)-tg²60=cos(60)-2√3sin(60)-tg²(60)=1/2-3-3=-5.5