sin(-x)=sin(x),cos(-x)=-cosx对吗?
sin(-x)=sin(x),cos(-x)=-cosx对吗?
sin(x+1/2π)=cosx?还是cos-x
sin(sin(sin(sin(x)=cos(cos(cos(cos(x),X等于多少?
f(x)=2cos*sin(x+π/3)-^3sin^2x+sinx*cosx
证明成立:[cos(3x)-sin(3x)]/(cosx+sinx)=1-2sin(2x).
sinx+cosx/sinx-cosx=2 求sinx/cos^3x +cosx/sin^3x
证明 tan(x+Δx)-tanx=sinΔx/cos(x+Δx)cosx
已知tan=2,求(cos x+sin x)/(cos x-sin x)+sin^2x
已知函数f(x)=2(sin^4 x+cos^4 x)+m(sin^x+cosx)^4在0=
高中数学已知函数f(x )=cos^2 x-√3 sin x cosx+2sin^2x-1/2
解下列方程 cos2x=cosx+sinx sin^4x-cos^4x=cosx+sinx
已知函数fx=[cosx+cos(π/2-x)][cosx+sin(π+x)]