x +y=90°,tanx*tany=?
证明 (tanX+tanY)/(tanX-tanY)=(sin(X+Y))/(sin(X-Y))
求证tanx+tany/tanx-tany=sin(x+y)/sin(x-y)(详细步骤)
cos(x+y)=1/5,cos(x-y)=3/5则tanx.tany=?
已知tanx=2,tany=3,x,y∈(0,π/2),求x+y.
已知sin(x+y)/cos(x-y)=m/n,则tanx/tany=?
sin(x+y)=1\2,sin(x—y)=1\3,求[tan(x+y)-tanx-tany]\[tany的平方tan(
tanx+tany=25 cotx+coty=30,那么tan(x+y)=?
已知tanx=2,tany=1/3,则tan2(x+y)=
tanx+tany=25,cotx+coty=30.tan(x+y)=?
tanX=2分之1,tan(x+y)=5分之2,那么tanY=?
已知tanx=1/4,tany=-3,求tan(x+y)的值
已知tanx=-3/4,且tan(x+y)=1,求tany的值