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: P_1(d) <-> t_3. forall y: R(y) -> P_1(y).
P_1(d) -> t_3 can be inferred via the biconditional elimination rule. t_3 -> P_1(d) can be inferred via the biconditional elimination rule.