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    (Original post by ns_2)
    A very, very good question - yes, I too have an issue with the diagram being misleading - however, a great test of ability.

    Can I send you the answer to confirm?
    Of course you may
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    (Original post by Y11_Maths)
    x
    Sorry you're right - I admit I cheated with your question and used Wolfram Alpha but I typed in a value wrong

    So I would write the question as

    "Show that \sin \theta = \frac{\sqrt{a}}{b} where a and b are integers."
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    (Original post by Notnek)
    Sorry you're right - I admit I cheated with your question and used Wolfram Alpha but I typed in a value wrong

    So I would write the question as

    "Show that \sin \theta = \frac{\sqrt{a}}{b} where a and b are integers."
    Ok, I will change the diagram so it looks more realistic and rearrange the final form to what you have specified. Thank you for your support Notnek
    and I will make sure to include you in any future questions I create. Thank you everyone
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    (Original post by Y11_Maths)
    I'm in year 11 and am targeted an 8 (but me and my teacher think I'll get a 9) and she thinks I'll get a B in the further maths GCSE. At first glance, it looks like a grade 9 question but for those who manage to make the first step it is easy enough. I think though, that most will struggle on making a start, not because it is hard but because it will scare them (the sin-1 and the surd)
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    (Original post by mundosinfin)
    This would definitely be 9, I'm predicted 9 and looking at this almost made me crap my pants. Let's hope this doesn't come up (or something similar)
    I’m f*cked.
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    (Original post by Baza2002)
    I'm in year 11 and am targeted an 8 (but me and my teacher think I'll get a 9) and she thinks I'll get a B in the further maths GCSE. At first glance, it looks like a grade 9 question but for those who manage to make the first step it is easy enough. I think though, that most will struggle on making a start, not because it is hard but because it will scare them (the sin-1 and the surd)
    Have you answered it?
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    (Original post by Y11_Maths)
    Have you answered it?
    no. ill do it tomorrow though
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    (Original post by Baza2002)
    no. ill do it tomorrow though
    Good luck when you do!
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    From this question, I don't get the inside sin function?

    I think grade 9 GCSE students will use the fact that sin(x)=sin(180-x) meaning sin(120) = sin(60). And that cos(120)=-cos(60): using the trig functions and the trig ratios introduced in the new spec.

    My solution:

    Spoiler:
    Show


    To avoid messy algebra:

    Let AB = a & AC therefore = 3a
    By the cosine rule BC = root [a^2 + 9a^2 - 2(3a^2)(cos120)]

    Note cos(120)=-cos(60)=-1/2

    Hence |BC| = root [10a^2+3a^2] --> |BC| = a root 13.

    Consider the sine rule:

    SinA/a = Sin120/a root 13

    SinA/a = root 3/2 / a root 13

    Simplify the RHS: SinA/a = root 3 / 2a root 13.

    This means that SinA = aroot 3 / 2a root 13 --> SinA = root 3 / 2 root 13. --> SinA = root 39 / 26 = 1/26 root 39.

    A = arcsin(1/26 root 39).

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    (Original post by thekidwhogames)
    From this question, I don't get the inside sin function?

    I think grade 9 GCSE students will use the fact that sin(x)=sin(180-x) meaning sin(120) = sin(60). And that cos(120)=-cos(60): using the trig functions and the trig ratios introduced in the new spec.

    My solution:

    Spoiler:
    Show


    To avoid messy algebra:

    Let AB = a & AC therefore = 3a
    By the cosine rule BC = root [a^2 + 9a^2 - 2(3a^2)(cos120)]

    Note cos(120)=-cos(60)=-1/2

    Hence |BC| = root [10a^2+3a^2] --> |BC| = a root 13.

    Consider the sine rule:

    SinA/a = Sin120/a root 13

    SinA/a = root 3/2 / a root 13

    Simplify the RHS: SinA/a = root 3 / 2a root 13.

    This means that SinA = aroot 3 / 2a root 13 --> SinA = root 3 / 2 root 13. --> SinA = root 39 / 26 = 1/26 root 39.

    A = arcsin(1/26 root 39).

    This is correct, how did you find the question difficulty wise when you were doing it? Also from start to finish how long did it take you?
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    (Original post by Y11_Maths)
    This is correct, how did you find the question difficulty wise when you were doing it? Also from start to finish how long did it take you?
    Difficulty wise, it's a solid grade 9 question.

    It took me about 2-3 minutes from start to finish though that could be because I'm no longer a GCSE Maths student and I spend a lot of time on hard problems.

    Very good question for grade 9 students! I can see this as the last question on a paper.
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    this is a level
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    (Original post by Abs Shocky)
    this is a level
    No, this would be a grade 9 GCSE question. What makes this A level? If anything, it'd be AS (A level has no trig like this).
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    Are you high? ahah No exam board would give a gcse student such nonesense in an exam. Because if they do. I'm ******* screwed on getting that grade 9... That isnt even on the syllabus...so don't know how you even found such a question lol
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    the funny thing is that will probs only be worth 3 or 4 marks
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    (Original post by thekidwhogames)
    Difficulty wise, it's a solid grade 9 question.

    It took me about 2-3 minutes from start to finish though that could be because I'm no longer a GCSE Maths student and I spend a lot of time on hard problems.

    Very good question for grade 9 students! I can see this as the last question on a paper.
    Bro, i think you're all a bit confused because this isbnt taught or in the gcse syllabus, wether you're a grade 9 student or not. So i'm a bit puzzled on why he's attempting these questions instead opf doing questions that will actually be in the paper???
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    (Original post by Somtochi)
    Bro, i think you're all a bit confused because this isbnt taught or in the gcse syllabus, wether you're a grade 9 student or not. So i'm a bit puzzled on why he's attempting these questions instead opf doing questions that will actually be in the paper???
    Mate, I'm not confused lol. I've already sat my GCSE and I'm telling you there are questions even much much harder than this. Take last year's Edexcel question on the cosine rule GCSE 9-1:

    https://www.thestudentroom.co.uk/sho....php?t=4740560

    This question (from this thread) would be a good grade 9 question. As you can see, both AQA and Edexcel have given even harder questions.

    Also, this is on spec GCSE syllabus. Nothing in this question required anything beyond cosine rule and sine rule (with algebra) hence a grade 9 question.
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    I'm predicted a grade 9. This took me around 10 minutes. It's a really good question and I can definitely see something like it coming up in the exams.
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    (Original post by 12tastani)
    standard deviation in a science exam!!! that shouldn't even be on the specification. We are allowed to sue for anything that's not legally on the spec. lol

    Further Maths though, has changed a lot! FP3 & FP4 stuff is in our CP1 (core pure 1 - 1st unit)
    It was essentially put under "Level 3 maths" in the spec - which is stupid sinc that could be anything from A Level.

    Our teacher did say it could come up, but so many people thought he was overreacting
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    (Original post by Kyber Ninja)
    It was essentially put under "Level 3 maths" in the spec - which is stupid sinc that could be anything from A Level.

    Our teacher did say it could come up, but so many people thought he was overreacting
    Chi squared tests are also in Biology.
 
 
 
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