若cos(π3−2x)=−78,则sin(x+π3)的值为( )
(2013•烟台二模)若cos(π3−2x)=−78,则sin(x+π3)的值为( )
已知f(x)=3cos(x+3π2)+cos(x−3π2)+sin(x+π)+a(a∈R,a为常数).
已知f(x)=(sin(π-x)*cos(2π-x))/cos(-π-x)*tan(π-x),则f(-31π/3)的值为
若f(cos x)=cos 2x,则f(sin 15度)的值?
当函数y=sin(π/3+x)cos(π-x)取得最大值时,tanx的值为
已知函数f(x)=−3sin2ωx+2sinωx•cosωx+3cos2ωx,其中ω>0,且f(x)的最小正周期为π.
已知f(x)=-1/2+sin(π/6-2x)+cos(2x-π/3)+cos平方x.
化简2sin^2[(π/4)+x]+根号3(sin^x-cos^x)-1
已知函数为f(x)=cos(2x-π╱3)+2sin(x-π/4)sin(x+π/4)
求证 tan(2π-X)sin(-2π-X)cos(6π-X)/ sin(X+3π/2)*cos(X+3π/2)=-ta
若tan x =3 则(sin 2x )/(cos方x +2)的值
若sin(π/2+x)=-4/5,x属于(π/2,π),则cos(π/3-x)=