What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: exists x: R_2(x) <-> P_2(x). forall x: ~Q(x). forall x: Q(x) <-> P_2(x).
forall x: Q(x) -> P_2(x) can be inferred via the universal biconditional elimination rule. exists x: R_2(x) -> P_2(x) can be inferred via the existential biconditional elimination rule. forall x: P_2(x) -> Q(x) can be inferred via the universal biconditional elimination rule. exists x: P_2(x) -> R_2(x) can be inferred via the existential biconditional elimination rule. forall x: ~P_2(x) can be inferred via the universal biconditional elimination rule.