已知sin(x+y)/cos(x-y)=m/n,则tanx/tany=?
已知sin(x+y)/cos(x-y)=m/n,则tanx/tany=?
证明 (tanX+tanY)/(tanX-tanY)=(sin(X+Y))/(sin(X-Y))
已知TanX,TanY是方程X^-3X-3=0的俩根,求sin^(x+y)-3sin(x+y)cos(x+y)-3cos
cos(x+y)=1/5,cos(x-y)=3/5则tanx.tany=?
求证tanx+tany/tanx-tany=sin(x+y)/sin(x-y)(详细步骤)
已知tanx,tany是方程x^2+6x+7=0的两个根,求证sin(x+y)=cos(x+y).
实数x,y满足tanx=x,tany=y,且|x|≠|y|,则sin(x+y)x+y−sin(x−y)x−y
若sin(x+y)=1/2,sin(x-y)=1/3,则tanx/tany等于?
tanX,tanY是方程X²+(4M+1)X+2M=0的俩根,且M≠-1/2求sin(X+Y)/cos(X-Y
若x、y是锐角且tanx=2/3tany=3/4则sin(x+y)等于
已知tanx,tany是方程x平方+Px+Q=0的两个根求sin(x+y)平方+
已知tanx,tany是方程x+6x+7=0的两个根,则tan(x+y) 已知cosθ=-1/2