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    Could somebody give me a STEP BY STEP working out of how to do this answer.

    Thanks in advance!
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    (Original post by greentron6)
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    Could somebody give me a STEP BY STEP working out of how to do this answer.

    Thanks in advance!
    For the first part just put 1 where t is
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    (Original post by Blake Jones)
    For the first part just put 1 where t is
    I know that! I'm talking about part b!
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    (Original post by greentron6)
    I know that! I'm talking about part b!
    haha yeah I'm working that one out in another tab - don't suppose you have an answer that you know is right do you? Got a method but not sure if it's right
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    (Original post by greentron6)
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    Could somebody give me a STEP BY STEP working out of how to do this answer.

    Thanks in advance!
    For the second part you know t must be less than 12 and h must be 9 so you can put in what you know to give 9=10+5sin(piT/6)
    you can then do 9-10 = -1 = 5sin(piT/6) and then
    sin^-1(-1/5)=piT/6 meaning in your next step you can do 6sin^-1(-1/5) / pi = T

    Do you know if in this question you're using radians or degrees?
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    (Original post by Blake Jones)
    For the second part you know t must be less than 12 and h must be 9 so you can put in what you know to give 9=10+5sin(piT/6)
    you can then do 9-10 = -1 = 5sin(piT/6) and then
    sin^-1(-1/5)=piT/6 meaning in your next step you can do 6sin^-1(-1/5) / pi = T

    Do you know if in this question you're using radians or degrees?
    really? it's obvious right?
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    (Original post by thefatone)
    really? it's obvious right?
    Yeah I thought so with the pi but thought it was worth checking
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    (Original post by Blake Jones)
    Yeah I thought so with the pi but thought it was worth checking
    i seem to get 11:22am as a time before midday, i can't find any others though :/

    Zacken
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    (Original post by Blake Jones)
    For the second part you know t must be less than 12 and h must be 9 so you can put in what you know to give 9=10+5sin(piT/6)
    you can then do 9-10 = -1 = 5sin(piT/6) and then
    sin^-1(-1/5)=piT/6 meaning in your next step you can do 6sin^-1(-1/5) / pi = T

    Do you know if in this question you're using radians or degrees?
    Apparently, the answer is = 0623, 1137. (The mark scheme says it will allow both radians or degrees, but i used radians).
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    (Original post by greentron6)
    Apparently, the answer is = 0623, 1137. (The mark scheme says it will allow both radians or degrees, but i used radians).
    \frac{\pi  T}{6} = \sin^{-1} \frac{1}{5}, \frac{\pi}{2} - \sin^{-1} \frac{1}{5}
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    (Original post by Zacken)
    \frac{\pi  T}{6} = \sin^{-1} \frac{1}{5}, \frac{\pi}{2} - \sin^{-1} \frac{1}{5}
    Could you actually give me a step by step explanation of how and why you got the answer?
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    (Original post by greentron6)
    Could you actually give me a step by step explanation of how and why you got the answer?
    What don't you understand about it? What have you tried?
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    (Original post by Zacken)
    What don't you understand about it? What have you tried?
    Yes, I tried it and I treated it as a trigonometric equation, however something went wrong after that. That's why was I want a step by step explanation, so I can identify my mistake.
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    (Original post by greentron6)
    Yes, I tried it and I treated it as a trigonometric equation, however something went wrong after that. That's why was I want a step by step explanation, so I can identify my mistake.
    Post what you've tried and we'll identify your mistake for you.
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    (Original post by Zacken)
    Post what you've tried and we'll identify your mistake for you.
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    (Original post by greentron6)
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    Everything up to \frac{\pi T}{6} = \sin^{-1}\left( -\frac{1}{5}\right)

    This has several solutions:

    \frac{\pi T}{6} = -0.201

    \frac{\pi T}{6} = \pi - - 0.201
    \frac{\pi T}{6} = -0.201 + 2\pi

    This gives (ignoring the negative solutions because time is positive):

    T = 3.684 and I'll let you do the other one. But 6.384 hours is 6 hours and 23 minutes after midnight.

    Can you do the other solution?
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    (Original post by Zacken)
    Everything up to \frac{\pi T}{6} = \sin^{-1}\left( -\frac{1}{5}\right)

    This has several solutions:

    \frac{\pi T}{6} = -0.201

    \frac{\pi T}{6} = \pi - - 0.201
    \frac{\pi T}{6} = -0.201 + 2\pi

    This gives (ignoring the negative solutions because time is positive):

    T = 6.684 and I'll let you do the other one. But 6.384 hours is 6 hours and 23 minutes after midnight.

    Can you do the other solution?
    Yes, thank you very much!
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    (Original post by greentron6)
    Yes, thank you very much!
    No problem.
 
 
 
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