求值: sin14π/3+ cos（﹣25π/4）=?

求值: sin14π/3+ cos（﹣25π/4）=? sin14/3π+cos（-23π/4）+tan（-25π/3）=? sin14/3π+cos（-23π/4）+tan（-25π/3）=? cos(3π/2 - π/3),求值 求值:cos(π/11)cos(2π/11)cos(3π/11)cos(4π/11)cos(5π/11) 求值：cos(π/11)-cos(2π/11)+cos(3π/11)-cos(4π/11)+cos(5π/11) 求值：cos²A+cos²（2π/3+A)+cos²(2π/3-A) cos（-8π/3）求值 cos（-8π/3）求值 求值:cos(arcsin√3/2)= 求值:cos(arcsin1/3) 化简-sin14分之5派*sin14分之3派*sin14分之派 已知tan(5π-α)=3求值sin（α﹣3π）+cos（π+α）／sin（﹣α）+cos（2π-α） 求值:cos(arcsin1/3)= COS(π/7)+COS(3π/7)+COS(5π/7)化简求值, 化简求值cos(π/7)cos(2π/7)cos(4π/7) 求值【sin(2π-α)sin(π+α)cos(-π-α)】/【sin(3π-α)-cos(π-α)】 已知cos(a+b)=0,求值:sin(π+2a+b)-cos(-π/2+2a+3b)