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Thread: Limit of ln(4x) as x --> 0+

  1. #1
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    Exclamation Limit of ln(4x) as x --> 0+

    solve the following limit,

    limit when x approaches 0 from the positive direction

    ln(4x)
    Last edited by mr fantastic; Oct 8th 2009 at 04:21 PM. Reason: Changed the post title
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  2. #2
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    diverges to $\displaystyle -\infty,$ do you see why?
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  3. #3
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    Exclamation derrivatives

    can you show me how you got that answer
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  4. #4
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    first note that $\displaystyle \ln4x=\ln4+\ln x$ so we'll worried about the $\displaystyle \ln x.$

    now consider $\displaystyle x=\frac19,$ or $\displaystyle \frac1{99}$ and so on.

    for small enough $\displaystyle x$ then using the fact that $\displaystyle \ln\frac1a=-\ln a$ yields the answer i gave.

    take a moment and think it for a while.
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