因为sin(α+β）=1,所以α+β=2kπ+π/2,tan(2α+β)+tanβ=tan(α+2kπ+π/2)+tan(2kπ+π/2-α)=
tan(α+π/2)+tan(π/2-α)=tan(α+π-π/2)+tan(π/2-α)=tan(α-π/2)+tan(π/2-α)=0