化简y=sin^2(x)+2sin(x)cos(x)+3cos^2(x)
化简y=sin^2(x)+2sin(x)cos(x)+3cos^2(x)
Sin x-sin y=2/3 cos x-cos y=1/2 求cos(x-y)
y =(cos^2) x - sin (3^x),求y'
sin(x+y)sin(x-y)=k,求cos^2x-cos^2y
求导f(x) = cos(3x) * cos(2x) + sin(3x) * sin(2x).
证明COS(X+Y)COS(X-Y)=COS^2X-SIN^2Y
y=sin^2x+sinxcoswx+cos^2x 化简
化简y=(cos x)^2+sin x -2 谢谢
已知tan=2,求(cos x+sin x)/(cos x-sin x)+sin^2x
化简 1/2cos x-根号3/2sin x 根3sin x+cos x
证明sin^2(x)+cos^2(x+30)+sin(x)cos(x+30)=3/4
y=sin^2(x)+2sin(x)cos(x)+3cos^2(x)的最值 用向量解