已知sin(x+y)=1/3,sin(x-y)=1/5,则tanx/tany

已知sinx=1/3,sin(x+y)=1,则sin（2y+x)= 已知sin(x+y)=1/3,sin(x-y)=1/5,则tanx/tany 已知Sin x+Sin y=1/2,Cos x+Cos y=根号3/3,求S求Sin(x-y)/2 已知sin(x+y)=1/2,sin(x-y)=1/3,求tanx,tany要不然我是看不懂的 已知sin(X+Y)=2/3,sin(X-Y)=1/5,求(tanX)/(tanY)的值 求导：y=3^(sin*1/x) Y=SIN(3x-1) 已知y=3sin(x+20)+5sin(x+80),求最大值? 已知y=3sin(x+20)+5sin(x+80)求最小值如题 已知cos(x-y/2)=-1/9,sin(x/2-y)=2/3,0 已知cos(x-y/2)=-1/9,sin(x/2-y)=2/3,0 已知sin（x+y）=1,求证：tan（2x+3y）=tany 已知x+y+z=π,证明sin(x+y)+sin(y+z)+sin(z+x)≥sin2x+sin2y+sin2z 求证sin²x-sin²y=sin(x+y)sin(x-y) sinx=1/3,sin(x+y)=1,求sin（2y+x）=? siny=1/3,sin(x＋y)=1,求sin(2x＋y) (cosx)^2-(cosy)^2=1/3求sin(x+y)*sin(x-y). sin^2x+cos^2y=1/2 求3sin^2x+sin^2y的最值