What is the Integral of ln(2x+1)?

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Homework Help Overview

The discussion revolves around finding the integral of the function ln(2x+1) with respect to x. Participants are exploring various techniques for integration, particularly focusing on integration by parts and substitution methods.

Discussion Character

  • Exploratory, Mathematical reasoning

Approaches and Questions Raised

  • Some participants attempt integration by parts, identifying u and dv, and expressing the integral in terms of these variables. Others suggest using u-substitution with u=2x+1 as a potentially simpler approach. There is also mention of simplifying the resulting integral through polynomial long division.

Discussion Status

The discussion is active, with participants sharing their attempts and suggesting alternative methods. There is no explicit consensus on the best approach, but multiple strategies are being explored, indicating a productive exchange of ideas.

Contextual Notes

Participants are working under the constraints of a homework assignment, which may limit the information they can provide or the methods they can use. The original poster's attempts and suggestions from others reflect a focus on understanding the integration process rather than arriving at a final answer.

Sczisnad
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Homework Statement


integral ln(2x+1)dx


Homework Equations


N/A


The Attempt at a Solution


I tried integration by parts,

Let u = ln(2x+1), dv = dx, du = 2/(2x+1)dx, v = x

ln(2x+1)dx = ln(2x+1)*x-(integral)x*(2/(2x+1))dx
 
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Try u-substitution with u=2x+1.
 
Sczisnad said:

Homework Statement


integral ln(2x+1)dx


Homework Equations


N/A


The Attempt at a Solution


I tried integration by parts,

Let u = ln(2x+1), dv = dx, du = 2/(2x+1)dx, v = x

ln(2x+1)dx = ln(2x+1)*x-(integral)x*(2/(2x+1))dx
So far, so good. The last integral can be turned into a simpler one by dividing 2x by 2x + 1, using polynomial long division. If you don't know that technique, it works out to 1 + -1/(2x + 1) in this problem.
 
Try u subsitution (the obvious one...)
 

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