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Thread: Ln X

  1. #1
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    Ln X

    Does (LN x)^3 = LN^3 x ?
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    Quote Originally Posted by kid funky fried View Post
    Does (LN x)^3 = LN^3 x ?
    It depends on the context. $\displaystyle ln^3(x)$ can either mean $\displaystyle ln(x) \cdot ln(x) \cdot ln(x)$ or it can mean $\displaystyle ln(ln(ln(x)))$, which are two very different things. I typically use it as the former expression, but there are cases where you would want to use it for the latter.

    Edit: By the way, note that the function is ln(x), not Ln(x) or LN(x). Mathematics (and Physics, and Engineering, and...) is a "case-sensitive" field of study.

    -Dan
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    Quote Originally Posted by kid funky fried View Post
    Does (LN x)^3 = LN^3 x ?
    It's not notation I'd use, but yes, I suppose it does.

    As long as you realise it's NOT LN (x^3)
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    thx

    thx.
    I will make sure to use the proper case next time.
    My answer book was using both expressions so i was beginning to wonder.
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  5. #5
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    In may be helpful to note that the notation $\displaystyle \left( {\ln \left( x \right)} \right)^n $ is used by almost all computer algebra systems.
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