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    • Thread Starter
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    Okay, we have this:



    But I thought log(a) + log(b) = log(ab), not log(a/b)

    Or am I being really silly?

    Thanks.
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    If you differentiate \dfrac{1}{K-N} you get -\ln |K-N| (since the coefficient of N is -1), hence the result... however it's not quite right, since you should have a constant of integration there (unless the constant on the RHS came from another integral).
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    (Original post by nuodai)
    If you differentiate \dfrac{1}{K-N} you get -\ln |K-N| (since the coefficient of N is -1), hence the result... however it's not quite right, since you should have a constant of integration there (unless the constant on the RHS came from another integral).
    I think it looks like a differential equation question, where they have to solve it. It also looks like they have gathered the constants, but didn't change the letter (which is what generally occurs).
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    It's because:

    Edit: People beat me to it =(
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    • Thread Starter
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    Pah, yea, realised it the second I posted it. Hmmm.... I'm not thinking right today. Thanks all.
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    (Original post by nuodai)
    If you differentiate \dfrac{1}{K-N} you get -\ln |K-N| (since the coefficient of N is -1), hence the result... however it's not quite right, since you should have a constant of integration there (unless the constant on the RHS came from another integral).
    Yea, the rhs came from another integral.
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    (Original post by nuodai)
    If you differentiate \dfrac{1}{K-N} you get -\ln |K-N| (since the coefficient of N is -1), hence the result... however it's not quite right, since you should have a constant of integration there (unless the constant on the RHS came from another integral).
    Careful:p:
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    (Original post by Slumpy)
    Careful:p:
    We all knew what he meant :p:
 
 
 
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