Solve each problem. (Modeling) Phase Angle of the Moon Because the moon o...

Solve each problem.

(Modeling) Phase Angle of the Moon Because the moon orbits Earth, we observe different phases of the moon during the period of a month. In the figure, t is the phase angle.

The phase F of the moon is modeled by

and gives the fraction of the moon’s face that is illuminated by the sun. (Source: Duffet-Smith, P., Practical Astronomy with Your Calculator, Cambridge University Press.) Evaluate each expression and interpret the result.