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: forall x_18: P_18(x_18) <-> Q_13(x_18). u_3 <-> Q_13(a_10). forall x_18: ~Q_18(x_18). u_3 or w. forall x_18: P_18(x_18) <-> Q_18(x_18).
u_3 -> Q_13(a_10) can be inferred via the biconditional elimination rule. Q_13(a_10) -> u_3 can be inferred via the biconditional elimination rule. forall x_18: P_18(x_18) -> Q_13(x_18) can be inferred via the universal biconditional elimination rule. forall x_18: P_18(x_18) -> Q_18(x_18) can be inferred via the universal biconditional elimination rule. forall x_18: Q_13(x_18) -> P_18(x_18) can be inferred via the universal biconditional elimination rule. forall x_18: Q_18(x_18) -> P_18(x_18) can be inferred via the universal biconditional elimination rule. forall x_18: ~P_18(x_18) can be inferred via the universal biconditional elimination rule.