Consider the following premises. exists x_18: T_4(x_18) or ~Q_2(x_18). forall x_18: T_4(x_18) <-> U_1(x_18). forall x_18: U_1(x_18) or Q_2(x_18). Can we infer forall x_18: ~(T_4(x_18) or P(x_18)) from them? If possible, name the inference rules being used at each step.
That contradicts the premises. Therefore the answer is no.