Translate the following inference to logic notation: There is at least one x for which if x_8 takes a plane, then x_8 is not a poet. For all x, x_8 is a poet if and only if x_8 is a doctor. For all x, x_8 is a doctor. Therefore there is at least one x for which x_8 will not take a plane.
exists x: P(x) -> ~Q(x). forall x: Q(x) <-> R(x). forall x: R(x). Therefore exists x: ~P(x).