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: R(x) -> Q(x). exists x: Q(x) -> R(x).
exists x: Q(x) <-> R(x) can be inferred via the existential biconditional introduction rule. exists x: R(x) <-> Q(x) can be inferred via the existential biconditional introduction rule.