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_6: P_6(x_6) or ~R(x_6). forall x_6: R(x_6) or R_3(x_6). forall x_6: P_6(x_6) <-> R_3(x_6).
forall x_6: R(x_6) -> P_6(x_6) can be inferred via the universal rewriting rule. forall x_6: P_6(x_6) -> R_3(x_6) can be inferred via the universal biconditional elimination rule. forall x_6: R_3(x_6) -> P_6(x_6) can be inferred via the universal biconditional elimination rule.