algebra

IT'S TIMED URGENT
A person sitting on a Ferris wheel rises and falls as the wheel turns. Suppose that the person's height above ground is described by the following function.
h(t)= 21.7 + 19.2 cos 1.4t

In this equation, h(t) is the height above ground in meters, t is the time in minutes.

Find the following. If necessary, round to the nearest hundredth.

Amplitude of h : __ meters

we know

-1 ≤ cos 1.4t ≤ 1 , no matter what the input for t is
then
-19.2 ≤ 19.2cos 1.4t ≤ 19.2

and the max of h(t) = 21.7+19.2 or 40.9
and the min of h(t) = 21.7 - 19.2 or 2.5

the amplitude = 1/2 (max - min) = 19.2
(which was obvious from the 19.2cos 1.4t )