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: w. p <-> u. ~p.
w and ~p can be inferred via the conjunction rule. ~p and w can be inferred via the conjunction rule. p -> u can be inferred via the biconditional elimination rule. u -> p can be inferred via the biconditional elimination rule. ~u can be inferred via the biconditional elimination rule.