Circadian Rhythms Circadian rhythm (from the Latin circa-about, and diem-day) is the daily biological pattern by which body temperature, blood pressure, and other physiological variables change. The data in the table below show typical changes in human body temperature over a 24-h period (
(a) Make a
(b) Find a cosine curve that models the data (as in Example 1).
(c) Graph the function you found in part (b) together with the scatter plot.
(d) Use a graphing calculator to find the sine curve that best fits the data (as in Example 2).
Time | Body temperature (
|
Time | Body temperature (
|
0 | 36.8 | 14 | 37.3 |
2 | 36.7 | 16 | 37.4 |
4 | 36.6 | 18 | 37.3 |
6 | 36.7 | 20 | 37.2 |
8 | 36.8 | 22 | 37.0 |
10 | 37.0 | 24 | 36.8 |
12 | 37.2 |
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