2cos30°+cot60°-2tan45°
=2*(1/2)+√3/3-2*(√2)/2
=1+√3/3-√2
sin的平方45°+cos的平方60°
=(√2/2)^2+(1/2)^2
=1/2+1/4
=3/4
sin的平方30°+cos的平方30°+cot的平方60°分之tan的平方60°
=(1/2)^2+(√3/2)^2+(√3)^2/(√3/3)^2
=1/4+3/4+3/(1/3)
=10