TRIG PROBLEM: Help me solve this, please. I will give Brainliest! Please show all work. I have no idea where to start :(

Let's start with part a, finding the maximum and minimum.

Answer a: Max temp is -5 C on day 200.  Min temp is -79 C on day 500.

Sine model.

We're looking for a model

T(n) = A sin( ωn - p ) + o

where T(n) is the estimated temperature on day n, A the amplitude of the variation, omega the radial frequency of variation, p a phase shift and o an offset, the average temperature.

Averaging min and max gives -42 C; that's the offset, what we get when the sine is zero.  o = -42 C.

That's pretty close to the value on day 0 so we'll just use a sine function without any phase shift, p = 0.

Subtracting min from max gives a total span of 74 C degrees, so a sinusoidal amplitude that's half that, A = 37 C.

From max to min is a half period, or about a half period since we're only seeing every 100 days.  That's 300 days, so a full cycle about every 600 days.

We want the argument to sine to go from 0 to 2pi as we complete a single period, 600 days,  So when n=600 this term must be 2π, so it's of the form

ωn = 2 π n / 600.

Putting it all together we get our model:

Answer b: T(n) = 37 sin(2 π n / 600) - 42

We already estimated the period at 600 days.  That's a full year.

Answer c: 600 days

We can see a full period is closer to 700 days (compare day 500 and day 1200, and also day 600 and day 1300) and the phase shift might need adjusting, but I think we pretty much did as they asked so I'll stop here.

the correct option is b

step-by-step explanation: