Consider the following premises. exists x_6: S(x_6) and U_1(x_6). forall x_6: Q(x_6). Can we infer forall x_6: ~(Q(x_6) and S(x_6)) from them? If possible, name the inference rules being used at each step.
 From exists x_6: S(x_6) and U_1(x_6) we can infer exists x_6: S(x_6) via existential simplification. Finally, from forall x_6: Q(x_6), exists x_6: S(x_6) we can infer exists x_6: Q(x_6) and S(x_6) via existential conjunction, which contradicts forall x_6: ~(Q(x_6) and S(x_6)). Therefore, the answer is no.