Starting at its rightmost position, it takes second for the pendulum of a grandfather clock to swing a
horizontal distance of 12 inches from right to left, and 1 second 1 for the pendulum to swing back from left
to right Write a cosine function, d = acos(bt), to model the distance, d, of the pendulum from the center
(in inches) as a function of time t (in seconds)
a =