√3cosπ/12-sinπ/12=

√3cosπ/12-sinπ/12= 若方程12x²+πx-12x=0的两的根分别是α,β,则cosαcosβ-√3sinαcosβ-√cosαsinβ-sinαsinβ= sinπ/12*cosπ/12=? sin(π/12)-cos(π/12)= 已知α=7/12π,那么cosα√（1-sinα）/(1+sinα)+sinα√（1-cosα）/(1-cosα)= sinπ/12-√3cosπ/12的值 根号3×cosπ／12－sinπ／12=? 化简sinπ/12-√3cosπ/12化简sinπ/12-√3cosπ/12 （cosπ/12 -sinπ/12）（cosπ/12 +sinπ/12）= (sinπ/12+cosπ/12)(sinπ/12-cosπ/12)= tanα=3,则sinα-cosα/2sinα+cosα等于多少-π/12等于多少 1.已知cosα=12/13,α∈(3π/2,2π),求cos(α+π/4).2.cos(α+β)=1/3,则(sinα-sinβ)^2+(cosα+cosβ)^2=?3.已知sinα=(√5)/5,sinβ=(√10)/10,α、β都是锐角,求cos(α+β)及α+β的值.4.已知锐角α、β满足sinα=(√5)/5,cosβ(√10)/1 sin(α+π/3)+sinα=负5分之4根号3 α∈（-π/2,0）求cosα怎样从9/4*sin²α=9/4(1-cos²α)=3/4*cos²a+12/5*cosx+48/25化为cos²α+4/5*cosα-11/100=0呀sin(α+π/3)+sinα=-4√3/5sinαcosπ/3+cosαsinπ/3+sinα=-4√3/53/2*si 化简 cos （π/12）+√3sin（π/12）= sin(5π/12)-√3cos(5π/12)= （sinπ/24)(cosπ/24)(cosπ/12) （sinπ/24)(cosπ/24)(cosπ/12) 请会的大哥大姐多多指教.已知sinθ=(√5-1)/4(1)求(sinθ-cosθ)/(sinθ+cosθ)+(sinθ+cosθ)/(sinθ-cosθ)的值.(2)已知5sinθ+12cosθ=0,求(sinθ+9cosθ)/2(2-3sinθ)的值.