求值:cos(25π /4)
求值:cos(25π /4)
求值:sin14π3+cos(−25π4)
求值:sin(-3分之19π)+cos(-6分之25π)=?
若cos(π/4+x)=3/5,求值
求值:sin(π/4+3x)cos(3/π-3x)+cos(π/6+3x)cos(π/4+3x)
求值:sin(π/12)+cos(π/12)
求值cos5π/8*cosπ8
求值sin25π/6+cos25π/3+tan(-25π/4)+sin(-7π/3)×cos(-13π/6)-sin(-
求值:1.cos(-14π/3) 2.tan(35π/6) 3.sin(-25π/6)
1.已知tan2分之α=2,求值:⑴ tan(α+4分之π);⑵ (6sinα+cosα)/(3sinα-2cosα)
求值tan(kπ+π/6)cos(kπ-4π/3),k属于z
求值:sin(π/4)cos(19π/6)tan(21π/4)急!