(1)tan(-1/5 π)与tan(-3/7 π)(2).

(1)tan(-1/5 π)与tan(-3/7 π)(2). 数学tan(α-π/2)=1/2 tan(π+β)=3 则 tan(α+β)=? tan(a+b)=3/4,tan(a-π/4)=1/2,那么tan(b+π/4)等于多少 怎么证明tan(π/(2k+1))×tan（2π/(2k+1))×tan(3π/(2k+1))×.tan(k/(2k+1 已知A、B是锐角,求证(tan(π+A)+tan(-B))/(1/tan(3π-A)+tan(π/2-B))=tanA* 1.已知tan(a+p)=2/5,tan(p-π/4)=1/4,则tan(a+π/4)=?2.已知sina=-1/3,a 已知sinθ=5分之3,θ∈(2分之π,π),tanψ=2分之1,求tan(θ+ψ),tan(θ-ψ)的值 已知Sin（a-（2n+1）π/2）=3/5 求tan a+1/tan a 已知2tanθ/1+tan^2θ=3/5,求sin^2(π/4+θ) tan(π/12)+1/tan(π/12)=啥? 化简：tan(π/8)+1/tan(π/12) tan(a-3/π) =2 tan(3/π-B)=2/5 求tan（a+b）=