计算cos(35°+x)cos(25°-x)-cos(55°-x)sin(25°-x)=______.
sin(sin(sin(sin(x)=cos(cos(cos(cos(x),X等于多少?
cos^2x+cos^2(x+120°)+cos^2(x+240°)
函数y=3sin(x+20°)+5cos(x-10°)的最大值是______.
证明COS(X+Y)COS(X-Y)=COS^2X-SIN^2Y
sin(-x) cos(-x)等于多少
化简sin(x-25°)sin(65°-x)+cos(x-25°)cos(65°-x)的结果为
化简cos²(-X)-【tan(360°+X)】/【sin(-X)】
函数y=sin(x+10°)+cos(x+40°),(x∈R)的最大值是______.
sin(x+105°)cos(x-15°)-cos(x+105°)sin求化简
cos(x+y)=?sin(x+y)=?
cos(2x+派/2)=sin(2x)?
化简cos(X-30°)+sin(X+30°)+cosX+1