Consider the following premises. forall x: R_3(x) -> R(x). forall x: R_3(x) or T_1(x). forall x: T_1(x) -> R(x). Can we infer forall x: R(x) from them? If possible, name the inference rules being used at each step.
We can infer forall x: R(x) via the universal disjunction elimination rule. Therefore, the answer is yes.