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 <-> R_23(a_23). u_3 <-> q_7. ~u_3. forall x_23: ~R_23(x_23).
u -> R_23(a_23) can be inferred via the biconditional elimination rule. u_3 -> q_7 can be inferred via the biconditional elimination rule. R_23(a_23) -> u can be inferred via the biconditional elimination rule. q_7 -> u_3 can be inferred via the biconditional elimination rule. ~q_7 can be inferred via the biconditional elimination rule.