The function to model the average high temperature for Buffalo, New York, by month t (with January as

To model the average high temperature H(t) as a cosine function, we'll use the general form:
![\[H(t) = A \cos(Bt - C) + D\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/3vjtmk3asq7yvpktvpy91g30m0nol9g3og.png)
Given:
- The average high temperature in July is
, which is the maximum value (amplitude) of the cosine function.
- The average high temperature in January is
, which will be the lowest value (minimum) of the cosine function.
- The pattern continues indefinitely, meaning it's a periodic function.
- We'll take January as t = 0 (starting point).
We need to determine the values of
to represent this cosine function.
The amplitude A is the difference between the maximum and minimum temperatures, so:
![\[A = \frac{\text{Max temperature} - \text{Min temperature}}{2} = (80 - 32)/(2) = 24\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/o8xh0gb0n404mruk1bv8w8wil7m446f1tb.png)
The period of the cosine function is the duration of the cycle, which is one year (12 months). Therefore, B relates to the frequency of oscillation:
![\[B = \frac{2\pi}{\text{period}} = (2\pi)/(12) = (\pi)/(6)\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/25cbq96nh9z8gforvs0x3y5qp87sbe0uiz.png)
The phase shift C is related to the horizontal shift of the cosine function. Since January is our starting point (t = 0), there is no phase shift (C = 0).
The vertical shift D shifts the entire function vertically. The midpoint between the maximum and minimum temperatures is the average of these values:
![\[D = \frac{\text{Max temperature} + \text{Min temperature}}{2} = (80 + 32)/(2) = 56\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/p9hlbf6gcjbw5p7suw1d5xq3iar682edkk.png)
Therefore, the function to model the average high temperature H(t) is:
![\[H(t) = 24 \cos\left((\pi)/(6)t\right) + 56\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/csa6styjaopa2zc82kk231nvw5ncm1pmnj.png)
This function represents the average high temperature for each month

Question:
The monthly high temperature for Buffalo, New York, peaks at an average high of
in July down to an average high of
in lanuary. Assume that this pattern for monthly high temperatures continues indefinitely and behaves like a cosine wave.
Write a function of the form
to model the average high temperature. The value
is the average high temperature for month
, with January as
.