The function f(x)=4.2cos(π/6(x−1))+13.7 models the average monthly temperature, where x is the number of the month (e.g., January = 1, December = 12), in a particular city.

Question

What is the average rate of change in temperature between January and March?

Answer 1

To find an average rate of change between x=a and x = b of y(x), you calculate the ratio (y(b)-y(a))/(b-a).

In this case a=1, b=3 and y(x) = f(x)