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    1/(1-x^2)^(3/2)


    i subbed in x = sinx

    1/(1-sinx^2)^(3/2)

    how do I get from the above to 1/cosx^3 ?
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    (Original post by IShouldBeRevising_)
    1/(1-x^2)^(3/2)


    i subbed in x = sinx

    1/(1-sinx^2)^(3/2)

    how do I get from the above to 1/cosx^3 ?
    Your basic C2 trig identities?

    What does 1 - \sin^2 x equal?
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    (Original post by justinawe)
    Your basic C2 trig identities?

    What does 1 - \sin^2 x equal?
    Cos^2x...
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    (Original post by IShouldBeRevising_)
    Cos^2x...
    there you have it
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    (Original post by justinawe)
    there you have it
    I know... how does

    1/cos^2x ^ (3/2) = 1/cos^3x
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    (Original post by IShouldBeRevising_)
    I know... how does

    1/cos^2x ^ (3/2) = 1/cos^3x
    (x^a)^b=x^{ab}
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    (Original post by Mr M)
    (x^a)^b=x^{ab}
    Thanks. Also do you have any idea when exam boards such as ocr are going to release examiner reports for the jan 2013 exams?
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    (Original post by IShouldBeRevising_)
    Thanks. Also do you have any idea when exam boards such as ocr are going to release examiner reports for the jan 2013 exams?
    Teachers like to use the most recent paper as a mock so the latest set of documents are not released to the public until the next examination season.
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    (Original post by Mr M)
    Teachers like to use the most recent paper as a mock so the latest set of documents are not released to the public until the next examination season.
    Ohhh... ok thank you.
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    (Original post by Mr M)
    Teachers like to use the most recent paper as a mock so the latest set of documents are not released to the public until the next examination season.
    Is that literally kicking in now? I was looking up some AEA resources at the weekend and was puzzled why the 2012 documents were listed as secure download when all the older stuff was directly downloadable. Today I've gone back in and the 2012 stuff is magically available
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    (Original post by davros)
    Is that literally kicking in now? I was looking up some AEA resources at the weekend and was puzzled why the 2012 documents were listed as secure download when all the older stuff was directly downloadable. Today I've gone back in and the 2012 stuff is magically available
    It's been the usual way things are done for ages although Awarding Bodies have been known to make up their policies as they go along ...
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    (Original post by Mr M)
    It's been the usual way things are done for ages although Awarding Bodies have been known to make up their policies as they go along ...
    Thanks...although you slightly misunderstood me - I really meant is "now" when the exam season is deemed to kick in?!
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    (Original post by davros)
    Thanks...although you slightly misunderstood me - I really meant is "now" when the exam season is deemed to kick in?!
    Depends on the frequency of the exam. I expect stuff examined in January will be made available to the public in late April/early May.
 
 
 
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