已知sin(x+y)=2/3,sin(x-y)=2/5,则tanx/tany的值是多少?

已知sinx=1/3,sin(x+y)=1,则sin（2y+x)= 已知(sinx)2-(siny)2=m求sin(x y)sin(x-y)求sin(x+y)sin(x-y) 已知Sin x+Sin y=1/2,Cos x+Cos y=根号3/3,求S求Sin(x-y)/2 3sin^2x+-2sin^2y=2sinx sin^2x+-sin^2y=? 已知sin(x+y)=1/3,sin(x-y)=1/5,则tanx/tany 已知sin(x)+3cos(x)=2,求sin(x)-cos(x)/sin(x)+cos(x)=? 已知sinx=3/5,x∈(π/2,π),求【sin(x+y)+sin(x-y)】/【cos（x+y）+cos（x-y）】的值 已知函数f(x) =√3cos(2x-y)-sin(2x-y) (0 已知sin(x+y)=2/3,sin(x-y)=2/5,则tanx/tany的值是多少? 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 已知tan=2,求(cos x+sin x)/(cos x-sin x)+sin^2x 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3sin^2x+2sin^2y=2sinx,则sin^2x+xin^2y的取值范围是 化简y=sin^2(x)+2sin(x)cos(x)+3cos^2(x) y=[sin^2(x)]*[sin^2(x)]求导 已知cos(x-y/2)=-1/9,sin(x/2-y)=2/3,0