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Differentiation C3

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    Am stuck on this..how to differentiate : log_2 (3x/x-1)

    If I could convert it to ln I should be able to do it but dunno how to convert it to ln


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    Do you know the change of base formula? Written in terms of ln it is:

    \log_a b = \dfrac{\ln b}{\ln a}
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    (Original post by notnek)
    Do you know the change of base formula? Written in terms of ln it is:

    \log_a b = \dfrac{\ln b}{\ln a}
    So ln(6x/x-1)? How do you differentiate that?
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    (Original post by Junaid96)
    So ln(6x/x-1)? How do you differentiate that?
    Use the log law:

    log \dfrac{A}{B} = \log A - \log B

    Or differentiate it directly using the normal method for finding the derivative of a natural logarithm. You need to use the quotient rule for that.
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    (Original post by notnek)
    Do you know the change of base formula? Written in terms of ln it is:

    \log_a b = \dfrac{\ln b}{\ln a}
    \log_a b = \dfrac{\ln b}{\ln a}

    oh that's it ..I had forgotten that
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    (Original post by arvin_infinity)
    \log_a b = \dfrac{\ln b}{\ln a}

    oh that's it ..I had forgotten that
    The general law works for any base:

    \log_a b = \dfrac{\log_c b}{\log_c a}

    If c is the number e then you have the law which I gave in my last post.
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    (Original post by notnek)
    The general law works for any base:

    \log_a b = \dfrac{\log_c b}{\log_c a}

    If c is the number e then you have the law which I gave in my last post.
    You are a legend
    This goes straight to my notes..
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    (Original post by arvin_infinity)
    You are a legend
    This goes straight to my notes..
    I don't mean to sound patronising, but why you have notes? I've never made notes for maths
    I always just did examples on paper and binned them afterwards - all the notes I need are neatly typed up in the textbook. It's pretty much the same for most people in my set, except most of them keep their example questions.
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    (Original post by Junaid96)
    I don't mean to sound patronising, but why you have notes? I've never made notes for maths
    I always just did examples on paper and binned them afterwards - all the notes I need are neatly typed up in the textbook. It's pretty much the same for most people in my set, except most of them keep their example questions.

    Yh that was last year when I got an A for math..this year need A*..it's v different
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    (Original post by arvin_infinity)
    Yh that was last year when I got an A for math..this year need A*..it's v different
    I also need an A*, but I don't find notes very useful at all, as maths is not something you can rote learn - you learn it by doing it. Practice is key

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Updated: June 10, 2012
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