Translate the following inference to logic notation: For all x, if x_9 drives a car, then x_9 is fast. There is at least one x for which x_9 is not happy. For all x, x_9 will drive a car if and only if x_9 is happy. For all x, if x_9 were fast, then x_9 is driving a car. Therefore there is at least one x for which x_9 is not fast.
forall x: P(x) -> Q(x). exists x: ~R(x). forall x: P(x) <-> R(x). forall x: Q(x) -> P(x). Therefore exists x: ~Q(x).