Sin x-sin y=2/3 cos x-cos y=1/2 求cos(x-y)
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
证明COS(X+Y)COS(X-Y)=COS^2X-SIN^2Y
化简y=sin^2(x)+2sin(x)cos(x)+3cos^2(x)
2sin^2x+cos^2y=1,求sin^2x+cos^2y的取值范围
sin^2x+cos^2y=1/2 求3sin^2x+sin^2y的最值
问道三角函数题已知sin(x)-sin(y)=-(2/3);cos(x)-cos(y)=(2/3);求cos(x-y)
求导y=(1+sin^2 x)/(cos(x^2))
已知函数y=(sin x+ cos x)(sin x+cos x)+2cos x*cos x ,求它的递减区间
求函数y =cos 2x +sin 2x /cos 2x -sin 2x 的最小正周期
Matlab编程问题 cos(x*y)*cos(x*(1-y))-0.5x*sin(x*y)*sin(x*(1-y))=