Convergence of the following integral

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Homework Help Overview

The discussion revolves around the convergence or divergence of the integral \(\int\frac{\ln(x)}{\sqrt[3]{x}(x+1)} \, dx\) from 1 to infinity, focusing on the behavior of the integrand as \(x\) approaches infinity.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants are exploring the use of comparison functions to determine convergence, specifically considering \(\ln(x)/x^{4/3}\) as a potential comparison. Questions arise about the behavior of this function and whether integration is necessary to establish convergence or divergence.

Discussion Status

The discussion is ongoing, with participants sharing thoughts on potential comparison functions and questioning the need for integration. There is no explicit consensus yet, but some guidance is being offered regarding the selection of comparison functions.

Contextual Notes

Participants are navigating the challenge of finding appropriate functions for comparison and are expressing uncertainty about the methods required to analyze convergence without resorting to integration.

Dell
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i need to prove that the following converges or diverges

[tex]\int[/tex][tex]\frac{ln(x)dx}{\sqrt[3]{x}(x+1)}[/tex] (from 1-∞)

what i have been trying to do is find a function that is either:
g(x)>f(x); g(x) converges
g(x)<f(x); g(x) diverges

but i have not been able,
is there any other way to solve this, or could you please show me a similar function that is one of the 2, if possible could you show how you reached your g(x)

thank you
 
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Hi Dell! :smile:

have you tried ∫ ln(x)/x4/3 dx ?
 
i thought of that, but what do i know about ln(x)/x^4/3, i would ideally liked to have taken it as my gx and said lim fx/gx=1 therefore f(x) behaves like ln(x)/x^4/3, how can i fin out if ln(x)/x^4/3 converges/diverges, do i have to integrate it? if so is there a simpler way than integration in parts? if not, is there not a simpler function you can think of
 
Dell said:
how can i fin out if ln(x)/x^4/3 converges/diverges, do i have to integrate it?

D'uh! :rolleyes:

you'd think so, wouldn't you?

get on with it!
 

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