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: ~u_3 or u. w_3 <-> u. u_3 or q_7. q_7 -> w_3.
q_7 or u can be inferred via the resolution rule. w_3 -> u can be inferred via the biconditional elimination rule. u -> w_3 can be inferred via the biconditional elimination rule.