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    for 9 iii I squared the side which had root3cosax only. Then I substituted in 3(1-sin^2ax) for that side. I cant remember if it was ax but would that gain any marks??? Please could you reply. I would really appreciate it. Thanks.
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    (Original post by ComputeiT)
    Using previous part:
    x^2/(x+4) = 3^2 = 9
    x^2=9(x+4)
    x^2=9x+36
    x^2-9x-36=0
    (x-12)(x+3)=0
    x=12 or -3

    But log base 3 (-3) is undefined.
    Therefore x = 12
    I originally thought this and put down my answer as x = 12. But then I realised that 2log3(-3) is the same as log3(9) [(-3)^2 = 9]. So isn't -3 allowed? If you do this on your calculator you get the correct answer. I'm not saying you're wrong I just don't understand why -3 isn't allowed.
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    (Original post by mrbeady9)
    I originally thought this and put down my answer as x = 12. But then I realised that 2log3(-3) is the same as log3(9) [(-3)^2 = 9]. So isn't -3 allowed? If you do this on your calculator you get the correct answer. I'm not saying you're wrong I just don't understand why -3 isn't allowed.
    Sketch a graph of log3(X)
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    (Original post by Mr M)
    \displaystyle \sum_{n=1}^{\infty} W_n = 1200

    \displaystyle \frac{N}{2}(2a+(N-1)d)>1200

    Let a = 5 and d = 1.5 and solve.
    I used both as the sum of the geometric series due to the previous question, will I get any marks do you think? I used the correct method throughout but didn't get a quadratic equation. I think I've averaged out at about 55 marks, should that be at least a C, I did want at least a B though.

    Thank you for your time.
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    (Original post by ArranJones)
    I used both as the sum of the geometric series due to the previous question, will I get any marks do you think? I used the correct method throughout but didn't get a quadratic equation. I think I've averaged out at about 55 marks, should that be at least a C, I did want at least a B though.

    Thank you for your time.
    If you found the sum to infinity was 1200, you'll get 1 mark. I doubt whether you'll get more credit as you completely misunderstood what you were expected to do.
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    (Original post by Mr M)
    If you found the sum to infinity was 1200, you'll get 1 mark. I doubt whether you'll get more credit as you completely misunderstood what you were expected to do.
    Okay then, thank you. I do understand the question. Just didn't do it properly in the exam, worst feeling ever!
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    (Original post by ArranJones)
    Okay then, thank you. I do understand the question. Just didn't do it properly in the exam, worst feeling ever!
    It's one question out of 6 modules. It won't prevent you from getting the grade you need in the end.
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    What was the question for 8iv?
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    if there a stats thread?
 
 
 
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