化简:cos(60-α)-cos(60+α)

化简:cos(60-α)-cos(60+α) cos(40)*cos(60)*cos(160) 化简cos(60°+α)= 化简：cos(60°-a)-cos(60°+a)= 化简：cos(60°+a)-cos(60°-a) 怎样化简cosαcos(60°-α)+1 化简:cos^2a-cos(a+60)cos(a-60)= 化简:cos^2A+cos^2(60°+A)+cos^2(60°-A) cos^2A+cos^2(A+60)-cosA*cos(A+60) 化简 化简:cos(-π-α) cos^2α+cos^2(α+π/3)-cosαcos(α+π/3)化简 sin30 60 45 cos Cos(-60°)=? cos 60°是多少 cos 【2cos³α-cos²α+cosα-2】/2cos²α+cosα+2化简 cos²(40°+α)+cos²(30°-α)+cos²(50°+α)×tan(60°-α)急急帮帮忙cos²(40°+α)+cos²(30°-α)+cos²(50°+α)×tan(60°-α) 化简 {sin(60+α )+cos120sinα}/cosα