Consider the following premises. forall x_9: Q_1(x_9) -> Q_9(x_9). forall x_9: ~U_2(x_9). forall x_9: U_2(x_9) <-> W_2(x_9). exists x_9: R(x_9) <-> Q_1(x_9). forall x_9: Q_9(x_9) -> W_2(x_9). Can we infer exists x_9: R(x_9) <-> Q_1(x_9) from them? If possible, name the inference rules being used at each step.
That is one of the premises. Therefore, the answer is yes.