Consider the following premises. forall x_15: P_15(x_15) or R_3(x_15). forall x_15: R_15(x_15) -> R(x_15). forall x_15: R_3(x_15) -> R(x_15). t -> ~R(g). forall x_15: ~P_15(x_15) or R_15(x_15). 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.