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: forall x: ~Q_2(x). exists x: S_4(x) <-> R(x). forall x: R(x) <-> W(x). forall x: W(x) <-> Q_2(x).
forall x: R(x) -> W(x) can be inferred via the universal biconditional elimination rule. forall x: W(x) -> Q_2(x) can be inferred via the universal biconditional elimination rule. exists x: S_4(x) -> R(x) can be inferred via the existential biconditional elimination rule. forall x: W(x) -> R(x) can be inferred via the universal biconditional elimination rule. forall x: Q_2(x) -> W(x) can be inferred via the universal biconditional elimination rule. exists x: R(x) -> S_4(x) can be inferred via the existential biconditional elimination rule. forall x: ~W(x) can be inferred via the universal biconditional elimination rule.