Translate the following inference to logic notation: For all x, x_6 is an astronaut or x_6 is not a musician. For all x, x_6 is a musician or x_6 is not an astronaut. Therefore for all x, x_6 is a musician if and only if x_6 is an astronaut.
forall x: P(x) or ~Q(x). forall x: Q(x) or ~P(x). Therefore forall x: Q(x) <-> P(x).