The daily low temperature in Guangzhou, China, varies over time in a periodic way that can be modeled by
a trigonometric function.
The period of change is exactly 1 year. The temperature peaks around July 26 at 78°F, and has its
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minimum half a year later at 49° F. Assuming a year is exactly 365 days, July 26 is per of a year after
January 1.
Find the formula of the trigonometric function that models the daily low temperature T in Guangzhout
years after January 1, 2015. Define the function using radians.
T(t) =(