化简cos(π/12-α)-根号3cos(5π/12+α)
化简cos(π/12-α)-根号3cos(5π/12+α)
化简cos(π/12)*cos(5π/12)
化简 (1+sinα+cosα)(sinα/2 -cosα/2) / 根号下 2+2cosα ,(3π/2
已知cos(π\3-2)=1\3,则cosα+根号3sinα=
化简:cos(-π-α)
已知sin(3π-α)=根号二cos(3π/2+β),根号三cos(-α)=负根号二cos(π+β),且0
已知cos(π/6-α)=根号3/3,求cos(5π/6+α)的值
化简cos平方α+cos平方(α-π/3)+cos平方(α+π/3) 急、~
计算cos(a+5π/12)cos(a+π/6)+cos(π/12-a)cos(π/3-a)
已知sinα-cosα=-根号5/5,π
根号3×cosπ/12-sinπ/12=?
求sin π/12-(根号3)cos π/12