sin(x+1/2π)=cosx?还是cos-x
sin(x+1/2π)=cosx?还是cos-x
f(x)=2cos*sin(x+π/3)-^3sin^2x+sinx*cosx
证明成立:[cos(3x)-sin(3x)]/(cosx+sinx)=1-2sin(2x).
已知函数fx=[cosx+cos(π/2-x)][cosx+sin(π+x)]
1、cos(x+B)*cos(x-B)=cosx-sin^2B
sin(-x)=sin(x),cos(-x)=-cosx对吗?
化简:1、sin(x-π/3)-cos(x+π/6)+√3cosx=?2、已知,sinα+sinβ=√2/2,求cosα
sinx+cosx/sinx-cosx=2 求sinx/cos^3x +cosx/sin^3x
设f=[sin(2/x)]=1+cosx,求f(x),f[cos(2/x)].
化简F(X)=2(COSX)^2+2 sin x cos x+1
高中数学已知函数f(x )=cos^2 x-√3 sin x cosx+2sin^2x-1/2
已知函数f(x)=【1-sin(x-3π/2)+cos(x+π/2)+tan3π/4】/cosx