Consider the following premises. forall x_15: Q_15(x_15). forall x_15: P_15(x_15) or ~Q_15(x_15). Can we infer ~P_15(a_9) from them?
 From forall x_15: P_15(x_15) or ~Q_15(x_15) we can infer forall x_15: Q_15(x_15) -> P_15(x_15). Finally, from forall x_15: Q_15(x_15) -> P_15(x_15), forall x_15: Q_15(x_15) we can infer forall x_15: P_15(x_15), which contradicts ~P_15(a_9). Therefore, the answer is no.