sin(α-π/6)=1/3,则cosα=

设角a=-35π/6,则2sin(π+α)cos(π-α)-cos(π+α)/ 1+sin^2α+sin(π-α)-cos^2(π+α)sina=sin(-35π/6)=sin(-6π+π/6)=1/2 cosα=根号3/22sin(π＋α)cos(π-α)-cos(π+α)/ [1+sin^2α+sin(π-α)-cos^2(π+α)]=2（-sinα)(-cosα）+cosα/[1+sin² 已知3sinα=cosα,则sinα-2sinαcosα+3cosα+1= 3sinα=2cosα,则 cosα-sinα/cosα+sinα/ cos3sinα=2cosα,则cosα-sinα/cosα+sinα/cosα+sinα/cosα-sinα 已知6sin²α+sinαcosα-2cos²α=0,α∈（π/2,π）,求值1).(sinα-3cosα）/（sinα-cosα）；2）.sinαcosα-sin²α;3).sin²α-3cosαsinα-2 若1+cosα/sinα=2 则cosα-3sinαRT... sinα+cosβ=1/2,则sin^3α+cos^3β= cos(π/3-α)=1/8,则cosα+（根号3）sinα的值为____已知cosα-cosβ=1/2,sinα-sinβ=1/3,求cos(α+β)的值 2sinα-3cosα/4sinα-9cosα=-1,则9sin^2α-3sinαcosα-5= 若sinα+sin^2α=1,则cos^2α+cos^6α+cos^8α=? sin α+sin^2α=1,则cos^2 α+cos^6 α+cos^8α=多少?, 若sinα+sin^2α=1,则cos^2α+cos^4α+cos^6α=? 已知cosα-cosβ=1/2,sinα-sinβ=-1/3,则cos(α-β)= 设sinα-sinβ=1/3,cosα+cosβ=1/2,则cos(α+β)=? sinαsinβ-cosαcosβ=-1/3则cos(2α+2β)=? 已知sinαsinβ-cosαcosβ=-1/3,则cos(2α+2β)=? 若cos(α-β)=1/3,则(sinα+sinβ)^2+(cosα+cosβ)^2=? 若cos( α-β)=1/3则 (sinα+sinβ )^2+(cosα+cosβ )^2rt sinα=-2cosα,求sin^2α-3sinαcosα+1