sin²x=(0.5-cos 2x)/2
sin²x=(0.5-cos 2x)/2
已知tan=2,求(cos x+sin x)/(cos x-sin x)+sin^2x
求导f(x) = cos(3x) * cos(2x) + sin(3x) * sin(2x).
已知函数f(x)=cos(2x-π\3)+sin²x-cos²x
sin²X-sinxcosx+2cos²x=
sin²x+sinxcosx+2cos²x=
a=(cos²x+sin²x,-2sinx),b=(cos²x-sin²x,co
MATLAB画图,y=sin(x)*(cos(x)-1)/((2*sin(x.^2)+4*cos(x)).^0.5)-(
化简y=sin^2(x)+2sin(x)cos(x)+3cos^2(x)
证明sin^2(x)+cos^2(x+30)+sin(x)cos(x+30)=3/4
求证:cos²x+cos²(x+a)-2cosxcosacos(x+a)=sin³a
求证(cos^2 x-sin^2 x)(cos^4 x+sin^4 x)+1/4 sin 2x sin 4x=cos 2