Is anyone knowledgeable in periodic functions? I am stuck on this question (Part a) that looks at the moon cycles and creating a mathematical model. Any help would be appreciated!

Question part a: http://imgur.com/a/oPjol

Question

Is anyone knowledgeable in periodic functions? I am stuck on this question (Part a) that looks at the moon cycles and creating a mathematical model. Any help would be appreciated!

Question part a: http://imgur.com/a/oPjol

tkhunny · Answer

Best results are obtained by showing YOUR work.

kodes · Answer

Thanks for that. I am quite aware. I was more looking for advice on finding the variables in y = a sin b(x+c) + d

dukelaxfan · Answer

Well A is the amplitude, d is vertical shift b is 2pi/b is period and c is phase shift

loser66 · Answer

I believe that you have a data. We need it.

kodes · Answer

Sorry, I will attach it to this message.

So far I have Y = 0.5 * Cos (PI 2/29.5) (x + c) + 0.5
But I don't know how to work out c and x.

loser66 · Answer

Pick any of them to put into Y to find c
Like if x = 8, y = 0.9 to find c