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_5: P_5(x_5) -> S(x_5). exists x_5: P_5(x_5) <-> S(x_5).
exists x_5: P_5(x_5) -> S(x_5) can be inferred via the existential biconditional elimination rule. exists x_5: S(x_5) -> P_5(x_5) can be inferred via the existential biconditional elimination rule.