In the tidal river, time between high and low tide is 6.2 hours. At high tide depth of water is 20.2 feet, where as at low tide depth is 5.6 feet. suppose water depth as function of time can be expressed by trigonometric function (sine or cosine).
Write the equation for depth f(t) of tide (in feet) t hours after 12:00 noon.
A boat needs the depth of 8 feet to set sail, and is docked at 12:00 noon. Find latest time in afternoon it can set sail?