Find the absolute maximum and absolute minimum of the function $\displaystyle f(x)=ln(3x)/x$ on the interval [0.1, 5]

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- Oct 25th 2009, 07:16 PM #1

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- Oct 25th 2009, 07:18 PM #2

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- Oct 25th 2009, 07:47 PM #3

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- Oct 25th 2009, 07:47 PM #4

- Oct 25th 2009, 08:31 PM #5

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- Oct 25th 2009, 08:32 PM #6

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- Oct 25th 2009, 09:49 PM #7

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Here is all I have so far.

Interval: [0.1, 5]

$\displaystyle f(x)=ln(3x)/x$

$\displaystyle f1(x)=(1-ln(3x))/(x^2)$

$\displaystyle x=e/3$

$\displaystyle f(.1)=-12.0397$

$\displaystyle f(5)=0.5416$

$\displaystyle f(e/3)=1.1036$

Max is $\displaystyle f(e/3)=1.1036$

Min is $\displaystyle f(.1)=-12.0397$

How close am I?

- Oct 26th 2009, 02:38 AM #8

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