若tan(x+y)=2tanx,求证3siny=sin(2x+y).
已知:3sinY=sin(2X+Y),求证tan(X+Y)=2tanX
已知5siny=sin(2x+y),求证:tan(x+y)=3/2tanx
3sinX=sin(2X+Y) 求证:tan(X+Y)=2tanX
tan(x+y)=2tanx(x,x+y≠kπ+π/2,k∈Z),证3siny=sin(2x+y)
求证:sin(x-y)/(sinx-siny)=cos[(x-y)/2]/cos[(x+y)/2]
sin(x+y)=1\2,sin(x—y)=1\3,求[tan(x+y)-tanx-tany]\[tany的平方tan(
已知sin(x+y)=1,求证:tan(2x+3y)=tany
证明sin(x+y)sin(x-y)=(sinx)^2-(siny)^2.
求证sinx+siny=2sin(x+y)/2*cos(x-y)/2
求证|sinx-siny|=|2sin[(x-y)/2]cos[(x+y)/2]|
求证:sin(2x+y)/sinx-2cos(x+y)=siny/sinx
求函数y=(tan²x-tanx+1)除以(tan²x+tanx+1)的值域 已知函数y=sin(2