Is f(x)=ln(x)/x Increasing or Decreasing?

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SUMMARY

The function f(x) = ln(x)/x is analyzed for its increasing and decreasing behavior, critical points, and concavity. The derivative, calculated as 1 - ln(x)/x², reveals critical points at (e, 1/e). The function exhibits an increase on the interval (0, e) and a decrease on (e, ∞). There are no local minima or inflection points, confirming that the local maximum occurs at (e, 1/e).

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Emma_011
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Find where increasing/decreasing, concavity, local extrema and inflection points for f(x)=ln/x

So here is what I have so far:

The derivative is 1-ln(x)/x^2

Critical points are (e,1/e)

No concavity

Local max is also (e,1/e) (no local min)

no inflection points

Increase on (0, e) and decrease on (e, positive infinity)

Is this correct? I tried to do a graph to justify my work
 
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Emma_011 said:
Find where increasing/decreasing, concavity, local extrema and inflection points for f(x)=ln x/x

The derivative is 1-ln(x)/x^2
Critical points are (e,1/e)
No concavity
Local max is also (e,1/e) (no local min)
Hi Emma, ☺

All correct so far.
Btw, how did you conclude that there is no concavity?

no inflection points
How did you reach that conclusion?
What is an inflection point exactly?

Increase on (0, e) and decrease on (e, positive infinity)

Correct.
 

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