tan(x+5π/4)=2 tanx=?
tan( x/2+π/4)+tan(x/2-π/4 )=2tanx
tan(X/2+π/4)+tan(x/2-π/4)=2tanx?
tanx+tan(π/2 -x)=?
证明sec x+tanx=tan(π/4 +x/2)
证明tanx+1/cosx=tan(x/2+π/4)
1)tan(x/2+π/4)+tan(x/2-π/4)=2tanx
tan(x/2+ π4)+tan(x/2- π/4)=2tanx
证明:tan(x+圆周率/4)=1+tanx/1-tanx
tan(x/2)=2.求tanx
证明下列恒等式(1)tan(x/2+π/4)+tan(x/2-π/4)=2tanx
求证:tan(x/2+π/4)+tan(x/2-π/4)=2tanx
求证:tan(x/2+派/4)+tan(x/2-派/4)=2tanx