
Finding a Trig Equation
Here is a picture of my question, just click on it to enlarge it. I need the equation to be sin. Here is an example from another question of the format of the formula.
5sin30(x1)+7
And here is the question
http://i25.tinypic.com/9rp2fo.jpg
This is extremely urgent, please help out.
Thanks alot.

You can run it through Excel or a lot of calculators and they'll do sine regressions. I used my ol' TI92 and got:
$\displaystyle y=1.085605sin(.907418x+.209669)0.229008$
For the second part of the problem, set the equation equal to 0.5 and solve for x.

K, i tried it and it didnt give the proper output numbers. I need the formula to include the axis, amplitude etc, if that helps.

That's all in your equation.The amplitude is obviously 1.085605.
The equation I gave gives the proper output. Not right on the money, but very close. That is as close as you can get.
For instance, if x=1.25, we get .829
Compare to .83 That's good.

It dosent work... For .5 i get a 21. The amplitude should equal .425... and there is no phase shift so i dont know what youre doing.

Not begging for an answer but this needs to be answered within about 6 hours.

Are you sure you're not in degrees. When I use .5, I get .439
.45 is what is in the chart. That is very close. Looking again, I do not see anything wrong. The data matches very close.
Using my equation we get
0 is .003
.5 is .44
.75 is .61
1.25 is .83
2.25 is .61
3 is .003
I do not know how you got 21 for x=.5
Those look close to me.
I suppose I am misunderstanding.
If you have something like $\displaystyle y=a\cdot{sin(bx+c)}$, then the period is $\displaystyle \frac{2\pi}{b}$ and the phase shift is $\displaystyle \frac{c}{b}$. The amplitude is a