Posted by Alex on .
Two consecutive days of the week experience a maximum temperature of 90 degrees F at 1:00pm and a minimum temperature of 44 degrees F at 1:00am. Write a cosine equation measured in house that would model this behavior. Let x=0 represent 1:00pm on the first day.

calculus 
Steve,
since the range is 4490, the amplitude is (9044)/2 = 23
The period is 24 hours, so
t = 23cos(2pi/24 x)+67
t(0) = 23cos(0)+67 = 23+67 = 90
t(12) = 23cos(2pi/24 * 12)+67 = 23cos(pi)+67 = 23+67 = 44