If tanθ1,tanθ2,tanθ3 and tanθ4 are the roots of the equation x4−x3 sin2β+x2cos2β−xcosβ−sinβ=0 then tan(θ1+θ2+θ3+θ4)=
If tan θ1, tan θ2, tan θ3 are the real roots of x3−(a+1)x2+(b−a)x−b=0 where θ1, θ2, θ3 are acute then θ1+θ2+θ3=