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_3 or ~w. w_3 <-> w.
w -> w_3 can be inferred via the rewriting rule. w_3 -> w can be inferred via the biconditional elimination rule. w -> w_3 can be inferred via the biconditional elimination rule.