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    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
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    The answer should be something close to 0.415..
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    (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.
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    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.
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    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
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    doesnt work,,,the tool is useless..thanks but didnt really help
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    (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.
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    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.
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    (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.
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    (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.
    :five:
 
 
 
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