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 minimum half a year later at 49∘F. Assuming a year is exactly 365 days, July 26 is 365206 of a year after January 1 .Find the formula of the trigonometric function that models the daily low temperature T in Guangzhou t years after January 1,2015 . Define the function using radians.T(t)=□
Q. 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 minimum half a year later at 49∘F. Assuming a year is exactly 365 days, July 26 is 365206 of a year after January 1 .Find the formula of the trigonometric function that models the daily low temperature T in Guangzhou t years after January 1,2015 . Define the function using radians.T(t)=□
Calculate Average Temperature: The average temperature is the midpoint between the maximum and minimum temperatures. Calculate the average: (78∘F+49∘F)/2.
Calculate Amplitude: The amplitude is half the distance between the maximum and minimum temperatures. Calculate the amplitude: (78°F−49°F)/2.
Calculate Angular Frequency: The period of the function is 1 year, which is 365 days. To find the angular frequency, use the formula ω=period2π. Calculate ω: 3652π.
Calculate Phase Shift: The function peaks at July 26, which is (206)/(365) of a year after January 1. To find the phase shift, use the formula φ=ω×(days after January 1). Calculate φ: 2π×(206)/(365).
Model Temperature Function: The trigonometric function that models the temperature is of the form T(t)=A⋅cos(ωt+φ)+D, where A is the amplitude, ω is the angular frequency, φ is the phase shift, and D is the average temperature. Substitute the values calculated in the previous steps.
Adjust Phase Shift: The function is T(t)=14.5×cos(3652πt+3652π×206)+63.5. However, we need to adjust the phase shift because the cosine function peaks at 0, and we want it to peak at 365206 of a year. To do this, we subtract the phase shift from π, not add it.
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