Solve
![-(Dv^2 + Dv1^2) H^2 + VDH^2 (Bx^2 + By^2 + Dv^2 - 2 By Dv Cos[θ] + 2 Bx Dv Sin[θ]) == 0](../HTMLFiles/index_167.gif){kind=small}
![-Dv Dv1 + (Bx Dv + By Dv1) Cos[θ] + (By Dv - Bx Dv1) Sin[θ] == 0](../HTMLFiles/index_168.gif){kind=small}
