Consider the following premises. forall x_11: P_3(x_11). exists x_11: Q_11(x_11). Can we infer forall x_11: ~(P_3(x_11) or P(x_11)) from them? If possible, name the inference rules being used at each step.
 From forall x_11: P_3(x_11), exists x_11: Q_11(x_11) we can infer exists x_11: P_3(x_11) and Q_11(x_11) via existential conjunction. From exists x_11: P_3(x_11) and Q_11(x_11) we can infer exists x_11: P_3(x_11) via existential simplification. Finally, from exists x_11: P_3(x_11) we can infer exists x_11: P_3(x_11) or P(x_11) via existential addition, which contradicts forall x_11: ~(P_3(x_11) or P(x_11)). Therefore, the answer is no.