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 y: R(y) or ~P(y). exists y: R(y) <-> P(y).
forall y: P(y) -> R(y) can be inferred via the universal rewriting rule. exists y: R(y) -> P(y) can be inferred via the existential biconditional elimination rule. exists y: P(y) -> R(y) can be inferred via the existential biconditional elimination rule.