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: ~S_14(a_14). ~r_4. forall x_14: Q_2(x_14) -> S_14(x_14). t <-> r_4.
~S_14(a_14) and ~r_4 can be inferred via the conjunction rule. ~r_4 and ~S_14(a_14) can be inferred via the conjunction rule. t -> r_4 can be inferred via the biconditional elimination rule. r_4 -> t can be inferred via the biconditional elimination rule. ~t can be inferred via the biconditional elimination rule.