证明sin2x+sin2y=2sin(x+y)cos(x-y)怎么做
若cosxcosy+sinxsiny=12,sin2x+sin2y=23,则sin(x+y)= ___ .
证明COS(X+Y)COS(X-Y)=COS^2X-SIN^2Y
请问怎么证明sinX+sin(X+Y)+sin(X+2Y)/cosX+cos(X+Y)+cos(X+2Y)=tan(X+
y=sin^2X+sin2X+3怎么求最值?
Y=sin^2x+sin2x+2cos^2x化简
1.y=cos^4x+sin^4x 求周期 2.y=(sin2x+sin(2x+π/3))/( cos2x+cos(2x
求函数 y=sin3x*sin^3x+cos3xcos^x/cos^22x +sin2x
求函数Y=sin^4x +cos^4x +sin^2x cos^2x 除以2-sin2x的最小正周期,最大值最小值
请问,如何证明sinx+siny=2*sin(x+y/2)*cos(x-y/2)
证明 [sin(2x+y)/sinx]-2cos(x+y)=siny/sinx
sin(x+y)-sinx=2cos(x+1/2y)sin(1/2y)的详细证明步骤.
sin(x+y)sin(x-y)=k,求cos^2x-cos^2y