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: q_6 <-> q_3. p_1 -> q_3. p_1.
q_3 can be inferred via the modus ponens rule. q_6 -> q_3 can be inferred via the biconditional elimination rule. q_3 -> q_6 can be inferred via the biconditional elimination rule.