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# Another one of those watch

1. 0= 1.85Sin (0.381 (1- C)) -1.25
2) 0-1.25 = 1.85Sin (0.381 (1- C))
3) 1.25 = 1.85Sin (0.381 (1- C))
4) 1.25÷ 1.85 = (0.381 (1- C))
5) Sin-1 (.676) = (0.381 (1- C))
6) 1- ( (Sin-1 (0.676)) ÷ 0.381) = C

im getting C= -0.948 ...Could someone see where im going wrong..Done this over and over
2. The answer should be something close to 0.415..
3. (Original post by Grunx)
0= 1.85Sin (0.381 (1- C)) -1.25
2) 0-1.25 = 1.85Sin (0.381 (1- C))
3) 1.25 = 1.85Sin (0.381 (1- C))
4) 1.25÷ 1.85 = (0.381 (1- C))
5) Sin-1 (.676) = (0.381 (1- C))
6) 1- ( (Sin-1 (0.676)) ÷ 0.381) = C

im getting C= -0.948 ...Could someone see where im going wrong..Done this over and over
Bold line is wrong.

Answer C=-0.947 is however correct rather than the answer in your second post.
4. I went through it again and got another answer : 1.061 but this is wrong again...It should be around 0.415..

Im using SinReg tool on my calculator and 0.415 is what comes up for C in the sinusoidal equation:y = Asin(B(x - C)) + D

When i calculate A,B,C and D , C seems to come up incorrect eventhough im using the right y and x values in the equation... SinReg tool gives me a different answer i i believe mine is wrong.
5. To end the discussion about what the answer is just type your equation in here....

http://www72.wolframalpha.com/

In fact, I'll do it for you...

http://www72.wolframalpha.com/input/...+C%29%29+-1.25
6. doesnt work,,,the tool is useless..thanks but didnt really help
7. (Original post by Grunx)
0= 1.85Sin (0.381 (1- C)) -1.25
2) 0-1.25 = 1.85Sin (0.381 (1- C))
3) 1.25 = 1.85Sin (0.381 (1- C))
4) 1.25÷ 1.85 = (0.381 (1- C))
5) Sin-1 (.676) = (0.381 (1- C))
6) 1- ( (Sin-1 (0.676)) ÷ 0.381) = C

im getting C= -0.948 ...Could someone see where im going wrong..Done this over and over
2)It should be 0+1.25
4) there should be a sin before the right hand side

You have however got the right answer.
8. I don't really want to give away the answer but your last thread everybody else did and you do seem to have the answer so:
Spoiler:
Show

add 1.25 to both sides.
divide both sides by 1.855
inverse sine both sides.
didivde both sides by 0.381
you're left with something like 1 -c = 1.9something then it's just obvious.
9. (Original post by Grunx)
doesnt work,,,the tool is useless..thanks but didnt really help
Who's going to break the news to Wolfram?

If you look at the plot it clearly shows a root close to -1 and no root near 0.415.

As the muon and I have said, you already have the correct answer.
10. (Original post by rnd)
Who's going to break the news to Wolfram?

If you look at the plot it clearly shows a root close to -1 and no root near 0.415.

As the muon and I have said, you already have the correct answer.

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