Since there is no independent source in the network V_TH = O V To find R_Th apply : A current source of 1 A across A and B. Apply KCL at node n₁ Apply KCL at node Vn₂ Vn₁ = 2V_x put in (i) ∴ Vn₂ = 4v_x put in (ii) 100 + V_x = 2V_x 100 = V_x ∴ Vn₂ = 4V_x = 400 V ∴ .