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iRaid
Jun14-11, 06:37 PM
1. The problem statement, all variables and given/known data
y=-2+sin((\frac{\Theta}{3})-(\frac{\pi}{12}))


2. Relevant equations


3. The attempt at a solution
http://img715.imageshack.us/img715/7707/trigg.png

Phase shift: \frac{\pi}{4}
Vertical shift: -2
Period: 6\pi

Mark44
Jun14-11, 07:12 PM
1. The problem statement, all variables and given/known data
y=-2+sin((\frac{\Theta}{3})-(\frac{\pi}{12}))


2. Relevant equations


3. The attempt at a solution
http://img715.imageshack.us/img715/7707/trigg.png

Phase shift: \frac{\pi}{4}
Vertical shift: -2
Period: 6\pi

Your graph is incorrect. When θ = 7π/4, y = -2 + sin(7π/12 - π/12) = -2 + sin(π/2) = -2 + 1 = -1. Your graph shows a y value of -2, not -1.

I think you might have done the stretch and phase shift in the wrong order, or maybe you did them in the right order but did your graph wrong.

iRaid
Jun14-11, 07:42 PM
Oh wow I misinterpreted it as a cosine graph (starting at high point rather than mid point).. Thank you.