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Outside temperature over a day can be modelled as a sinusoidal function. Suppose you know the high temperature for the day is 95 degrees and the low temperature of 75 degrees occurs at 6 AM. Assuming t is the number of hours since midnight, find an equation for the temperature, D, in terms of t.

User Cmcginty
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Answer:

Yes, a sinusoidal function is a great way to model temperatures over a 24-hour period because the pattern of temperature changes tends to be cyclic.

A sinusoidal function can be written in the general form:

D(t) = A sin(B(t - C)) + D

where:

- A is the amplitude (half the range of the temperature changes)

- B is the frequency of the cycle (which would be `2π/24` in this case because the temperature completes a full cycle every 24 hours)

- C is the horizontal shift (which is determined by the fact that the minimum temperature occurs at 6 AM)

- D is the vertical shift (which is the average of the maximum and minimum temperature)

Given the information you've provided, let's fill in the specifics:

- The high temperature for the day is 95 degrees.

- The low temperature is 75 degrees at 6 AM.

The amplitude, A, is half the range of temperature changes. It's the difference between the high and the low temperature divided by 2:

A = (95 - 75) / 2 = 10

The frequency, B, is `2π/24` because the temperature completes a full cycle every 24 hours.

The horizontal shift, C, is determined by the fact that the minimum temperature occurs at 6 AM. The sine function hits its minimum halfway through its period, so we want to shift the function to the right by 6 hours to make this happen. In our case, this means C = 6.

The vertical shift, D, is the average of the maximum and minimum temperature:

D = (95 + 75) / 2 = 85

So the equation for the temperature, D, in terms of t (the number of hours since midnight) is:

D(t) = 10 sin((2π/24) * (t - 6)) + 85

This equation represents a sinusoidal function that models the temperature over a day given the information provided.

User John Jeffery
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