Consider the following premises. ~Q_12(a_11). forall x_12: Q_12(x_12) -> P_12(x_12). forall x_12: P_12(x_12) -> Q_12(x_12). w_2 -> P_12(a_11). Can we infer ~u from them? If possible, name the inference rules being used at each step.
We cannot infer that from the premises. Therefore the answer is no.