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    https://www.youtube.com/watch?v=Dl9DOikeb0k

    https://qualifications.pearson.com/content/dam/pdf/A%20Level/Mathematics/2013/Exam%20materials/6665_01_pef_20120307.pdf

    Edexcel Core Maths C3 January 2012 Q8c

    I don’t understand how to get the second solution. According to the explanation, (pi-theta) > (theta-pi/6). But why?

    If someone can explain this small step to me, I understand how to do the rest of my answer.
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    (Original post by HumzaAhmed)
    https://www.youtube.com/watch?v=Dl9DOikeb0k

    https://qualifications.pearson.com/content/dam/pdf/A%20Level/Mathematics/2013/Exam%20materials/6665_01_pef_20120307.pdf

    Edexcel Core Maths C3 January 2012 Q8c

    I don’t understand how to get the second solution. According to the explanation, (pi-theta) > (theta-pi/6). But why?

    If someone can explain this small step to me, I understand how to do the rest of my answer.
    From what I can see you use what they tell you in part B. Divide through by (√3−x) and then that bit on the left is equal to tan(x+π/6). The just arctan both sides and solve for theta.
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    (Original post by wa17)
    From what I can see you use what they tell you in part B. Divide through by (√3−x) and then that bit on the left is equal to tan(x+π/6). The just arctan both sides and solve for theta.
    Arctan on both sides will get you the first solution. How does that lead to the second solution?
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    Note that tan is a periodic function where generally:

     \displaystyle \tan(\theta) = \tan(\theta + n \pi), \quad \text{where n is an integer}.

    So in this case:

     \displaystyle \tan(\pi - \theta) = \tan((\pi - \theta) + \pi).
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    (Original post by simon0)
    Note that tan is a periodic function where generally:

     \displaystyle \tan(\theta) = \tan(\theta + n \pi), \quad \text{where n is an integer}.
    Yep I understand that. Its just that in order to use that, you need to know which angle is smaller and which angle is larger.
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    (Original post by HumzaAhmed)
    Yep I understand that. Its just that in order to use that, you need to know which angle is smaller and which angle is larger.
    No you don't.
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    (Original post by Prasiortle)
    No you don't.
    I get it now becuase the response was edited.
 
 
 
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