Question

The number of hours of daylight in Vancouver can be modelled by a
sinusoidal function of time, in days. The longest day of the year is
June 21, with 15.7 h of daylight. The shortest day of the year is
December 21, with 8.3 h of daylight.
a) Find an equation for n(t) the number of hours of daylight on the
nth day of the year.
I wanna know how one determines if it is going to be a sin or cosine function.

Answer 1

in some courses, the primary setup is sin

Answer 2

other than that ... it doesnt really matter

Answer 3

or have a misread your question

Answer 4

can it be both sine and consine?

Answer 5

cosine*

Answer 6

you can model it both ways yes. but by convention i believe it is modeled as:

y = A sin(w(x-h)) + k

Answer 7

sin and cosine are phase shifts of each other by 90 degrees .... so which one you actually use is immaterial

Answer 8

okay so when in doubt always do sin?

Answer 9

when in doubt, use what youre comfortable with :)

Answer 10

haha okay, cuz i was thinking since this question will start off with the max point why not do cosine. but the answer at back does sin.

Answer 11

then work the cos, and phase shift it into sin

Answer 12

i'll do both so i get comfortable with both of them